Weather Blog: Showers today, then Nice Weather then Active Weather

Posted at 12:59 PM, May 11, 2021
and last updated 2021-05-11 14:09:45-04

Good Tuesday bloggers,

We have a series of weather changes to track between today and Sunday. Just today we have seen a series of weather changes as the day started with light rain followed by 1-2 hours of a partly to mostly sunny sky. This will be followed by lots of clouds and the chance of scattered rain showers.

Let's go through the forecast. At the end we will show a rainfall forecast map for the next 7 days followed by the percentage of average rainfall during the last 30 days. You may be surprised.

Scattered small showers will be possible, mainly 3-10 PM. If you get underneath one expect 10-15 minutes of rain and even the chance of a 2-5 minute very heavy downpour. Temperatures will be in the 50s to low 60s.


These will be nice days under a partly to mostly sunny sky. Lows will be in the 40s with highs in the 60s. The clouds and showers will be pushed west by a slow moving surface high tracking from eastern Iowa to the Great Lakes.


A weak system and cold front will drop in from the northwest. It will bring a chance of showers and thunderstorms as a cold front approaches. The showers and thunderstorms will likely weaken as they approach as the cold front maintains its importance. Highs will be in the 60s.


The Friday cold front will stall and begin wavering north-south as a series of disturbances track out of the Rockies. This will set up a zone of thunderstorms each day. These will not be all day rain events, but timing the thunderstorms will have to be taken one day at a time. The timing of the thunderstorms will be set by the yet to be determined location of the front and track/timing of the disturbances.

The threat of severe weather is much lower than the threat of flash flooding as the flow aloft is not that strong. That being said, it is May, the peak of severe weather season, so we must NEVER let our guard down even when the severe threat is low.


You can see on this data, the GFS, also known as the "American Model", it has the zone of heavy rain along and north of I-70. The location of the heavy rain zone is not set yet. It could shift north or south by 50-100 miles. Around the heavy rain zone amounts will be .25" to 1". Also, most of this rain occurs Saturday-Monday.


Now, you see the rainfall forecast map above. Hopefully, it is right as it would cover some dry areas. Here in KC we do not need the rain, but look at all the areas that do. This is a map of the percent average rainfall during the last 30 days. We are at 107% with Des Moines at 34%. Many areas along and west of I-35 could use a nice drink of water. The above rainfall forecast does have the more significant rain south of Des Moines.


When we zoom in, the rainfall disparity is even more glaring. Locations along and east of I-35 and south of I-70 have seen 70% to 140% of average rainfall. Locations west of I-35 and north of I-70 have seen 25% to 70% of average rainfall. The driest areas are located from northeast Kansas to northwest Missouri. Maryville sits at just 28% of average rainfall during the last 30 days.

The corn growing season has begun and the newly planted seeds could use a drink of water. If the rain this weekend plays out like it is shown above, then there will be many happy corn seeds.

This dryness has not been severe enough to have these areas in a drought index. But, if it does not rain much the 10 days that could change.

Yes, the broader map has us at 107% average and the close in map has us at 77% to 82% of average. The broader data may be using a slightly different time period. The bottom line is that rain is needed northwest of KC.


Have a great rest of your week and stay healthy.