Good Saturday bloggers,
The high heat and humidity is 48 hours from being pushed away by a strong summer cold front. The Excessive Heat Warning expires at 8 PM tonight and should not return for awhile. Now, tomorrow will still be a steam bath, but not quite as hot due to clouds. The high heat will shift south, but still be rather close to I-70.
The Excessive Heat Warning today extends all the way to the east coast and this cold front will wipe that off the map by Tuesday.
The cold front early Saturday morning was located just north of I-80 then southwest to eastern Colorado. There have been some pretty heavy thunderstorms up there. Look at Pierre, SD, 59° degrees. This front means business. There is a surface low in southwest Nebraska and this is due to a developing system coming from the monsoon in the southwest USA. Let’s track the progress of the system and front, as it is the system that may enhance rainfall around here.
SATURDAY AFTERNOON: The front will be sagging slowly south to around I-80 as the surface low sags south. We will have another hot, very humid and windy day with dangerous heat index values around 110°.
SUNDAY MORNING: Thunderstorms will be widespread around the front. Southern Nebraska, southern Iowa into northern Missouri will see some very heavy rain. A thunderstorm may sneak into KC, but the chance is low. Lows will be 75°-80° once again. The front will now extend from northern Missouri to the surface low west of Salina, KS.
SUNDAY AFTERNOON: Here we go! The front will be quite close to I-70 as the surface low is drifting east near Salina. The stifling heat and humidity will be from KC south and east, while temperatures will be in the 70s across Nebraska. The atmosphere is ready to explode with thunderstorms and you can see the new development between Grand Island, NE and Concordia, KS.
SUNDAY NIGHT: This data has a huge area of very heavy rain and thunderstorms. There is still uncertainty on how widespread the heavy rain will be and also the exact track. But, given the amount of heat and humidity and the presence of a strong summer cold front along with a system in the upper levels, it stands to reason that a large area of heavy rain and thunderstorms will affect most areas.
MONDAY: Regardless of where the heavy rain sets up, we will all experience incredible heat relief. A surface high pressure in the northern Plains will deliver much cooler and much less humid air south. Highs on Monday will be around 80° and this is where lows have been the last several days. The high heat should stay away for some time as another cold front arrives at the end of the week into next weekend.
We are getting close to one month where some areas have hardly had any rain. The areas that have seen the big rainfall totals saw most of that occur on July 4th, so all locations could use a nice soaking. Now, some areas may see 5″ of rain tomorrow night and that is too much all at once, so flash flooding could be an issue. The rainfall rates in the heaviest thunderstorms could reach 2″ to 3″ per hour.
Have a great weekend!
Jeff Penner
