Past Features
This page lists out the IEM Daily Features for a month at a time. Features have been posted on most days since February 2002. List all feature titles.
Tue Apr 01, 2025
Windy March Days
01 Apr 2025 05:30 AM
Compared with most days this March, winds were not all that bad yesterday to end the month. The featured chart presents the number of days each March with a daily peak wind gust of at least 30 MPH at Mason City (NC Iowa). The 19 days this year is the most since at least 1973. While some data exists prior to 1973 for the site, observation techniques and reporting were different prior to then making longer term comparisons a bit tricky. That aside, it is interesting to see each of the past six years above a recent trend line and longer term average. A common refrain from Iowans is that it is windier now than in the past, but authoritatively answering that statement with observed data is difficult.
Voting: Good - 11 Bad - 3
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01 Apr 2025 05:30 AM
Compared with most days this March, winds were not all that bad yesterday to end the month. The featured chart presents the number of days each March with a daily peak wind gust of at least 30 MPH at Mason City (NC Iowa). The 19 days this year is the most since at least 1973. While some data exists prior to 1973 for the site, observation techniques and reporting were different prior to then making longer term comparisons a bit tricky. That aside, it is interesting to see each of the past six years above a recent trend line and longer term average. A common refrain from Iowans is that it is windier now than in the past, but authoritatively answering that statement with observed data is difficult.
Voting: Good - 11 Bad - 3
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Wed Apr 02, 2025
Four Days of Moderate Risks
02 Apr 2025 05:33 AM
The Weather Prediction Center (WPC) issues an Excessive Rainfall Outlook, which is akin to the Storm Prediction Center's (SPC) Convective Outlook with similar threat levels. This outlook for the next four days has a moderate risk forecast for approximately the same location over the mid Mississippi Valley region. The featured image presents these four outlooks as they are currently forecast this Wednesday morning. The outlook for Thursday even has a high risk area delineated, which like the SPC high risk, is reserved for the most extreme of events. Forecast rainfall totals over this period are expected near ten inches with isolated higher amounts approaching fifteen inches and perhaps even more.
Voting: Good - 22 Bad - 1
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02 Apr 2025 05:33 AM
The Weather Prediction Center (WPC) issues an Excessive Rainfall Outlook, which is akin to the Storm Prediction Center's (SPC) Convective Outlook with similar threat levels. This outlook for the next four days has a moderate risk forecast for approximately the same location over the mid Mississippi Valley region. The featured image presents these four outlooks as they are currently forecast this Wednesday morning. The outlook for Thursday even has a high risk area delineated, which like the SPC high risk, is reserved for the most extreme of events. Forecast rainfall totals over this period are expected near ten inches with isolated higher amounts approaching fifteen inches and perhaps even more.
Voting: Good - 22 Bad - 1
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Thu Apr 03, 2025
Hours of 20+ MPH
03 Apr 2025 05:30 AM
Winds on Wednesday were once again quite windy with gusts topping 50 MPH for some parts of the state. So the daily feature is once again attempting to quantify if this year has been windier than average or even the windiest on record as many Iowans continue to believe. The featured chart presents the number of hours for the year to date period with a sustained wind speed of at least 20 MPH. While this year's value falls just outside of the top 10, it certainly is above average with the bottom panel showing the hourly frequency above average for nearby all of the daylight hours of the day. Of course, there is no one simple metric to answer the question on how windy it has been this year. This website certainly offers a number of "autoplot" tools to investigate this yourself as you can follow the "generate chart" button on this feature and turn knobs until you find 2025 on top!
Voting: Good - 13 Bad - 0
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03 Apr 2025 05:30 AM
Winds on Wednesday were once again quite windy with gusts topping 50 MPH for some parts of the state. So the daily feature is once again attempting to quantify if this year has been windier than average or even the windiest on record as many Iowans continue to believe. The featured chart presents the number of hours for the year to date period with a sustained wind speed of at least 20 MPH. While this year's value falls just outside of the top 10, it certainly is above average with the bottom panel showing the hourly frequency above average for nearby all of the daylight hours of the day. Of course, there is no one simple metric to answer the question on how windy it has been this year. This website certainly offers a number of "autoplot" tools to investigate this yourself as you can follow the "generate chart" button on this feature and turn knobs until you find 2025 on top!
Voting: Good - 13 Bad - 0
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Fri Apr 04, 2025
Finding Highs in the 50s
04 Apr 2025 05:30 AM
Early April can be a frustrating time in Iowa as a long cold season has everyone ready for great spring weather, but chilly temperatures are still quite possible and the growing season is not fully started yet. The near term forecast has daily high temperatures mostly in the 50s for the next number of days, so today's featured chart looks into which months have the highest frequency of such days for Ames. It turns out that April has the highest frequency of such days, but you notice a rapid drop off for May and the frequency is basically zero for the summer months of June through August.
Voting: Good - 11 Bad - 3
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04 Apr 2025 05:30 AM
Early April can be a frustrating time in Iowa as a long cold season has everyone ready for great spring weather, but chilly temperatures are still quite possible and the growing season is not fully started yet. The near term forecast has daily high temperatures mostly in the 50s for the next number of days, so today's featured chart looks into which months have the highest frequency of such days for Ames. It turns out that April has the highest frequency of such days, but you notice a rapid drop off for May and the frequency is basically zero for the summer months of June through August.
Voting: Good - 11 Bad - 3
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Mon Apr 07, 2025
Pleasant April Afternoon
07 Apr 2025 05:30 AM
The featured map presents a simple analysis of airport temperature observations from 6 PM on Sunday (23 UTC). It was a rather pleasant April afternoon with not too much wind, sunshine and temperatures shown in the 50s to lower 60s. Chillier air will start off the work week today with warmer temperatures and chances of rain by the end of the week. After lamenting if we can avoid any further winter season weather and have some spring before summer arrives by the daily features last week, it appears this week will be just that with some in-between those two seasons weather.
Voting: Good - 5 Bad - 0
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07 Apr 2025 05:30 AM
The featured map presents a simple analysis of airport temperature observations from 6 PM on Sunday (23 UTC). It was a rather pleasant April afternoon with not too much wind, sunshine and temperatures shown in the 50s to lower 60s. Chillier air will start off the work week today with warmer temperatures and chances of rain by the end of the week. After lamenting if we can avoid any further winter season weather and have some spring before summer arrives by the daily features last week, it appears this week will be just that with some in-between those two seasons weather.
Voting: Good - 5 Bad - 0
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Tue Apr 08, 2025
2025 YTD Precipitation
08 Apr 2025 05:30 AM
It is as good of a time as any to check in on year to date precipitation accumulations. The featured chart does just that for Ames, presenting the yearly accumulated value for this year, last year, the driest and wettest years along with the climatology. This year is sitting right at about average, but running well behind the 2024 total for the same year to date period. In some regards, what happens for the first three months of the year does not matter much as the totals are meager compared with the upcoming main precipitation months, which can make or break the year total. You can see that there isn't all that much spread between the various lines by the first week of April. Interestingly, you can see how closely 2024 tracked 1993 up until July.
Voting: Good - 16 Bad - 0
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08 Apr 2025 05:30 AM
It is as good of a time as any to check in on year to date precipitation accumulations. The featured chart does just that for Ames, presenting the yearly accumulated value for this year, last year, the driest and wettest years along with the climatology. This year is sitting right at about average, but running well behind the 2024 total for the same year to date period. In some regards, what happens for the first three months of the year does not matter much as the totals are meager compared with the upcoming main precipitation months, which can make or break the year total. You can see that there isn't all that much spread between the various lines by the first week of April. Interestingly, you can see how closely 2024 tracked 1993 up until July.
Voting: Good - 16 Bad - 0
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Wed Apr 09, 2025
Checking Soil Moisture
09 Apr 2025 05:30 AM
As mostly guided by crop insurance dates, the start of the production agriculture growing season in Iowa is just mere days away. So it is a good time to check in on soil moisture analyses with today's featured chart presenting ERA5Land based soil water estimated within the top 1 meter of soil for a location near Ames. With data back to 1950, a climatology is produced along with the 2025 value. The ERA5Land data source is delayed by about seven days, so the bit of rain on 2 April isn't shown within the 2025 data yet. That issue aside, a drier than average situation to start off March has improved some during the month, which is the typical case shown by increasing climatolgy as limited evaporation and no plant usage allow for March rains to efficiently replenish soil moisture. April has gotten off to a decent start moisture wise, but totals over the next seven days look meager.
Voting: Good - 6 Bad - 0
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09 Apr 2025 05:30 AM
As mostly guided by crop insurance dates, the start of the production agriculture growing season in Iowa is just mere days away. So it is a good time to check in on soil moisture analyses with today's featured chart presenting ERA5Land based soil water estimated within the top 1 meter of soil for a location near Ames. With data back to 1950, a climatology is produced along with the 2025 value. The ERA5Land data source is delayed by about seven days, so the bit of rain on 2 April isn't shown within the 2025 data yet. That issue aside, a drier than average situation to start off March has improved some during the month, which is the typical case shown by increasing climatolgy as limited evaporation and no plant usage allow for March rains to efficiently replenish soil moisture. April has gotten off to a decent start moisture wise, but totals over the next seven days look meager.
Voting: Good - 6 Bad - 0
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Thu Apr 10, 2025
Red Flag Warning Duration
10 Apr 2025 05:30 AM
NWS Sioux Falls issued a Red Flag Warning (Fire Weather) Wednesday for its forecast area, which includes a number of Northwestern Iowa counties. The featured chart looks into the duration of these warning events based on the office's warnings since 2006. The plotted lines represent the accumulated frequency of warning events at a given time duration value. An event is a single warning for a single county / forecast zone. The plot nicely shows these events are generally between four and eight hours in duration, which covers the windiest and least humid portion of the daylight day. Shorter duration events are typically covered by other messaging, like the Special Weather Statement and longer duration events are typically not possible with subsiding winds as the boundary layer stabilizes, cools, and increases with humidity.
Voting: Good - 11 Bad - 1
Tags: firewx
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10 Apr 2025 05:30 AM
NWS Sioux Falls issued a Red Flag Warning (Fire Weather) Wednesday for its forecast area, which includes a number of Northwestern Iowa counties. The featured chart looks into the duration of these warning events based on the office's warnings since 2006. The plotted lines represent the accumulated frequency of warning events at a given time duration value. An event is a single warning for a single county / forecast zone. The plot nicely shows these events are generally between four and eight hours in duration, which covers the windiest and least humid portion of the daylight day. Shorter duration events are typically covered by other messaging, like the Special Weather Statement and longer duration events are typically not possible with subsiding winds as the boundary layer stabilizes, cools, and increases with humidity.
Voting: Good - 11 Bad - 1
Tags: firewx
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Fri Apr 11, 2025
Early Morning Fun
11 Apr 2025 05:30 AM
For early risers Thursday morning, you may have noticed some interesting weather around central Iowa with a rapid warm up just before sunrise. The featured chart presents one minute observations from the ISU Soil Moisture station just west of Ames between 4 and 7 AM. Of immediate notice is the jump in temperature from about 41°F to 55°F about thirty minutes later. A couple of things were happening at the time to explain this rapid temperature change. First, a frontal passage happened with chinook winds behind the front. The bottom panel nicely shows the wind shift to just north of west, which is a favored direction for such events. The second thing happening was very warm air just above the surface, which was being forced downward by stray shower activity. Perhaps some would say this was a heat burst type event, but it wasn't the only thing driving the rapid temperature change.
Voting: Good - 13 Bad - 1
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11 Apr 2025 05:30 AM
For early risers Thursday morning, you may have noticed some interesting weather around central Iowa with a rapid warm up just before sunrise. The featured chart presents one minute observations from the ISU Soil Moisture station just west of Ames between 4 and 7 AM. Of immediate notice is the jump in temperature from about 41°F to 55°F about thirty minutes later. A couple of things were happening at the time to explain this rapid temperature change. First, a frontal passage happened with chinook winds behind the front. The bottom panel nicely shows the wind shift to just north of west, which is a favored direction for such events. The second thing happening was very warm air just above the surface, which was being forced downward by stray shower activity. Perhaps some would say this was a heat burst type event, but it wasn't the only thing driving the rapid temperature change.
Voting: Good - 13 Bad - 1
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Mon Apr 14, 2025
April Dryness Stripe
14 Apr 2025 05:30 AM
The featured map presents month to date precipitation departures based on PRISM estimates compared with a NOAA gridded climatology. The departures are expressed as a percentage of average with values below 100% indicating drier than average. The map analysis shows a dry stripe stretching from Omaha to northeastern Iowa. Only a few isolated pockets are indicated above average. While southern Iowa has seen improvements to the drought situation going into this growing season, other parts of the state could certainly use some significant rainfall over the coming weeks. The near term forecast does have a few chances of precipitation, but the heaviest totals look to remain well to our south.
Voting: Good - 14 Bad - 1
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14 Apr 2025 05:30 AM
The featured map presents month to date precipitation departures based on PRISM estimates compared with a NOAA gridded climatology. The departures are expressed as a percentage of average with values below 100% indicating drier than average. The map analysis shows a dry stripe stretching from Omaha to northeastern Iowa. Only a few isolated pockets are indicated above average. While southern Iowa has seen improvements to the drought situation going into this growing season, other parts of the state could certainly use some significant rainfall over the coming weeks. The near term forecast does have a few chances of precipitation, but the heaviest totals look to remain well to our south.
Voting: Good - 14 Bad - 1
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Tue Apr 15, 2025
Hard Freeze after April 15th
15 Apr 2025 05:30 AM
The hope that we are done with very cold temperatures increases each day as April progresses, but the featured map shows the reality that for most of Iowa, a hard freeze (low temperature below 29°F) is still more likely than not. The map presents the percentile that April 15th resides at for having the last such daily cold low temperature of the season. Rewording, a value of 50 indicates that 50 percent of years have seen the final sub 29°F by April 15. So values below 50 indicate that more years than not have seen such a cold temperature after the date. A caveat for the plot as micro-climates at individual stations and local topography can significantly influence this metric, but the chart shows the general signal. Much of the state has a number of weeks to go before such cold temperatures become a rare event.
Voting: Good - 15 Bad - 3
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15 Apr 2025 05:30 AM
The hope that we are done with very cold temperatures increases each day as April progresses, but the featured map shows the reality that for most of Iowa, a hard freeze (low temperature below 29°F) is still more likely than not. The map presents the percentile that April 15th resides at for having the last such daily cold low temperature of the season. Rewording, a value of 50 indicates that 50 percent of years have seen the final sub 29°F by April 15. So values below 50 indicate that more years than not have seen such a cold temperature after the date. A caveat for the plot as micro-climates at individual stations and local topography can significantly influence this metric, but the chart shows the general signal. Much of the state has a number of weeks to go before such cold temperatures become a rare event.
Voting: Good - 15 Bad - 3
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Wed Apr 16, 2025
IEM Daily Archiving
16 Apr 2025 05:30 AM
The IEM attempts to archive a lot of data each day. The goal being to make accessible long term archives available for both funded research projects that support the IEM and also for anybody else to freely use. This archiving activity takes on a number of different forms with a "flat file" directory tree being the subject of today's Daily Feature. This directory tree is organized by UTC date and subsequent sub-folders. The predictable and stable URLs allow for automated downloads and scraping. The featured chart presents the daily total of archived file size, the accumulated storage, and some annotated dates explaining why the archive sizes increased at that time. There are some practical constraints to archival capacity, so the scope of archival has not changed much over the past five years or so. There is an associated ISU project called MTArchive with a similar directory structure, but archives more meteorological specific datasets. MTArchive also has a different funding model, so thus why the service is separate.
Voting: Good - 22 Bad - 0
Tags: iem archive
16 Apr 2025 05:30 AM
The IEM attempts to archive a lot of data each day. The goal being to make accessible long term archives available for both funded research projects that support the IEM and also for anybody else to freely use. This archiving activity takes on a number of different forms with a "flat file" directory tree being the subject of today's Daily Feature. This directory tree is organized by UTC date and subsequent sub-folders. The predictable and stable URLs allow for automated downloads and scraping. The featured chart presents the daily total of archived file size, the accumulated storage, and some annotated dates explaining why the archive sizes increased at that time. There are some practical constraints to archival capacity, so the scope of archival has not changed much over the past five years or so. There is an associated ISU project called MTArchive with a similar directory structure, but archives more meteorological specific datasets. MTArchive also has a different funding model, so thus why the service is separate.
Voting: Good - 22 Bad - 0
Tags: iem archive
Thu Apr 17, 2025
SPC MCD Watch Probability
17 Apr 2025 05:30 AM
Iowa is forecast to have a chance of severe weather today and into the overnight hours. As the event unfolds, the Storm Prediction Center (SPC) issues Mesoscale Convective Discussions (MCD)s [example MCD text] that provide up to the minute forecast details and thinking from the experts at the SPC. The MCD product sometimes portends an upcoming Tornado or Severe Thunderstorm Watch. As a part of that process, the MCD will contain a watch issuance probability (a fixed percentage value of 5, 20, 40, 60, 80, or 95 percent). So the featured chart compares this forecast value to if a watch was issued in the near term future (within 2.5 hours) for a spatially coincident area outlined by the MCD. The archive for this probability exists back to 2012 and there's an IEM portal to download the archive. Remarkably, the 60, 80, and 95 percent thresholds seem in high agreement with only a few percentage points difference between the two. The 20 percent threshold may be suffering from this arbitrary time and space threshold combination or maybe it is not well calibrated, this crude and unofficial IEM analysis wishes not to state anything absolutely.
Voting: Good - 8 Bad - 1
Tags: spc mcd
17 Apr 2025 05:30 AM
Iowa is forecast to have a chance of severe weather today and into the overnight hours. As the event unfolds, the Storm Prediction Center (SPC) issues Mesoscale Convective Discussions (MCD)s [example MCD text] that provide up to the minute forecast details and thinking from the experts at the SPC. The MCD product sometimes portends an upcoming Tornado or Severe Thunderstorm Watch. As a part of that process, the MCD will contain a watch issuance probability (a fixed percentage value of 5, 20, 40, 60, 80, or 95 percent). So the featured chart compares this forecast value to if a watch was issued in the near term future (within 2.5 hours) for a spatially coincident area outlined by the MCD. The archive for this probability exists back to 2012 and there's an IEM portal to download the archive. Remarkably, the 60, 80, and 95 percent thresholds seem in high agreement with only a few percentage points difference between the two. The 20 percent threshold may be suffering from this arbitrary time and space threshold combination or maybe it is not well calibrated, this crude and unofficial IEM analysis wishes not to state anything absolutely.
Voting: Good - 8 Bad - 1
Tags: spc mcd
Fri Apr 18, 2025
Tornado Emergency
18 Apr 2025 05:30 AM
A couple of very strong super-cell thunderstorms worked into southwestern Iowa early Thursday evening and produced a number of tornadoes. One of the storms promoted NWS Omaha to issue a Tornado Emergency for Essex, IA, which is just northeast of Shenandoah. These are a special class of Tornado Warnings with a known significant tornado headed for a populated location. The featured map presents the unofficial tally of such Tornado Emergencies for locations in Iowa. It is a rather rare occurrence. The IEM has a page that shows lists out these events along with Flash Flood Emergencies.
Voting: Good - 29 Bad - 1
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18 Apr 2025 05:30 AM
A couple of very strong super-cell thunderstorms worked into southwestern Iowa early Thursday evening and produced a number of tornadoes. One of the storms promoted NWS Omaha to issue a Tornado Emergency for Essex, IA, which is just northeast of Shenandoah. These are a special class of Tornado Warnings with a known significant tornado headed for a populated location. The featured map presents the unofficial tally of such Tornado Emergencies for locations in Iowa. It is a rather rare occurrence. The IEM has a page that shows lists out these events along with Flash Flood Emergencies.
Voting: Good - 29 Bad - 1
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Mon Apr 21, 2025
Easter Record
21 Apr 2025 05:30 AM
The weather was wet and dreary for Easter Sunday, but much needed rainfall was received over the eastern half of Iowa. The official observation for Des Moines recorded 0.97" inches, while not a calendar day record precipitation, it was an unofficial record total for Easter Sunday according to IEM calculations as shown by the featured chart. The second highest total shown was only a few years ago back in 2020.
Voting: Good - 14 Bad - 0
Tags: easter
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21 Apr 2025 05:30 AM
The weather was wet and dreary for Easter Sunday, but much needed rainfall was received over the eastern half of Iowa. The official observation for Des Moines recorded 0.97" inches, while not a calendar day record precipitation, it was an unofficial record total for Easter Sunday according to IEM calculations as shown by the featured chart. The second highest total shown was only a few years ago back in 2020.
Voting: Good - 14 Bad - 0
Tags: easter
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Tue Apr 22, 2025
Near term GDDs
22 Apr 2025 05:30 AM
The weekly USDA NASS update showed Iowa off to a fast start with corn planting this season with an estimated 18% of the state now planted. The much needed rainfall over the Easter weekend has likely helped these newly planted seeds proceed with germination. Accumulated growing degree days (GDD) now bear monitoring to speed this process along. The featured chart looks into this with recent computed GDDs for Des Moines along with two forecasts, a simple period of record daily climatology, and accumulated values since 13 April plotted as well. There is certainly a lot going on with this chart, but it would indicate an above average accumulation over the near term period. As is typically the case this time of year, some days can have rather meager accumulations with chilly weather and others can be at the other extreme. Of course, too much early development can be a bad thing as it increases freeze risk damage as we still have a few weeks to be generally clear of most climatological risks of damaging freezes.
Voting: Good - 8 Bad - 0
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22 Apr 2025 05:30 AM
The weekly USDA NASS update showed Iowa off to a fast start with corn planting this season with an estimated 18% of the state now planted. The much needed rainfall over the Easter weekend has likely helped these newly planted seeds proceed with germination. Accumulated growing degree days (GDD) now bear monitoring to speed this process along. The featured chart looks into this with recent computed GDDs for Des Moines along with two forecasts, a simple period of record daily climatology, and accumulated values since 13 April plotted as well. There is certainly a lot going on with this chart, but it would indicate an above average accumulation over the near term period. As is typically the case this time of year, some days can have rather meager accumulations with chilly weather and others can be at the other extreme. Of course, too much early development can be a bad thing as it increases freeze risk damage as we still have a few weeks to be generally clear of most climatological risks of damaging freezes.
Voting: Good - 8 Bad - 0
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Wed Apr 23, 2025
Earth Day 2025
23 Apr 2025 05:30 AM
The 22nd of April is Earth Day and the weather yesterday in Iowa was quite nice for April. The featured chart presents an info-graphic of some climate metrics contained within the National Weather Service Climate Report (CLI) for Cedar Rapids. The statistical extras found on the high and low temperature dials are based on period of record observations for the site. Precipitation metrics for the site are looking decent with April above average and the year to date period not far behind average. More rainfall chances are in the near term forecast.
Voting: Good - 18 Bad - 0
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23 Apr 2025 05:30 AM
The 22nd of April is Earth Day and the weather yesterday in Iowa was quite nice for April. The featured chart presents an info-graphic of some climate metrics contained within the National Weather Service Climate Report (CLI) for Cedar Rapids. The statistical extras found on the high and low temperature dials are based on period of record observations for the site. Precipitation metrics for the site are looking decent with April above average and the year to date period not far behind average. More rainfall chances are in the near term forecast.
Voting: Good - 18 Bad - 0
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Thu Apr 24, 2025
April CDDs
24 Apr 2025 05:30 AM
Wednesday felt a bit like early summer with afternoon temperatures near 80°F, a noticeable increase in humidity, and some festering late afternoon thunderstorms. The featured chart presents monthly Cooling Degree Days (CDD)s for Des Moines since 2006. The start year of the chart has no significance other than to keep the plot legible. CDDs can be computed in a number of ways, but for the purpose of this chart it is simply the average daily temperature minus 60°F and always at least zero in value, so no negative numbers. CDDs are difficult to accumulate during April due to overnight low temperatures typically being well below 60°F and thus pulling the average significantly down. The chart remarkably shows the largest value during the first four month of the year period happening during the epic warmth of March 2012!
Voting: Good - 11 Bad - 1
Tags: cdd
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24 Apr 2025 05:30 AM
Wednesday felt a bit like early summer with afternoon temperatures near 80°F, a noticeable increase in humidity, and some festering late afternoon thunderstorms. The featured chart presents monthly Cooling Degree Days (CDD)s for Des Moines since 2006. The start year of the chart has no significance other than to keep the plot legible. CDDs can be computed in a number of ways, but for the purpose of this chart it is simply the average daily temperature minus 60°F and always at least zero in value, so no negative numbers. CDDs are difficult to accumulate during April due to overnight low temperatures typically being well below 60°F and thus pulling the average significantly down. The chart remarkably shows the largest value during the first four month of the year period happening during the epic warmth of March 2012!
Voting: Good - 11 Bad - 1
Tags: cdd
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Fri Apr 25, 2025
60°F+ Dew Points
25 Apr 2025 05:30 AM
The increase in humidity this week has certainly be noticeable and has helped to support numerous rounds of showers and thunderstorms. The dew point temperature for Des Moines topped out at 60°F on Thursday and such dew points are the subject of today's daily feature. The top panel presents a simple climatology of daily max dew point along with the 2025 observations. The bottom panel shows the daily frequency of having such a maximum dew point of at least 60°F. So the overall frequency this time of year is around 10%, but you can see how quickly the frequencies increase through May into June as plant transpiration, evaporation, and warming temperatures all help to support higher humidity levels.
Voting: Good - 14 Bad - 1
Tags: dewpoint
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25 Apr 2025 05:30 AM
The increase in humidity this week has certainly be noticeable and has helped to support numerous rounds of showers and thunderstorms. The dew point temperature for Des Moines topped out at 60°F on Thursday and such dew points are the subject of today's daily feature. The top panel presents a simple climatology of daily max dew point along with the 2025 observations. The bottom panel shows the daily frequency of having such a maximum dew point of at least 60°F. So the overall frequency this time of year is around 10%, but you can see how quickly the frequencies increase through May into June as plant transpiration, evaporation, and warming temperatures all help to support higher humidity levels.
Voting: Good - 14 Bad - 1
Tags: dewpoint
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