Joe’s Weather World: Watching Friday’s storms…and more summer weather coming (THU-9/26)
It’s going to be a really nice fall day in the KC region. We’ve started the day with a low of 55° and we should finish well into the 70s…with low dew points. The dew point situation will change overnight and when you wake up tomorrow you’ll feel that summer humidity again.
This is ahead of a cold front that will move through later tomorrow. That front coming into the building heat and high dew points will allow storms to develop quickly and in some cases rather strongly. There is a risk of severe weather…mainly from the Metro southwards…we’ll be tracking that front tomorrow because it will be a big player in the severe weather risk.
Several metro high school football games have been rescheduled due to a high storm probability.
Post frontal storms/rains are likely and may be heavy tomorrow night into Saturday AM at least.
Today: Mostly sunny with highs 75-80°
Tonight: Increasing clouds and windy conditions developing with lows 65° but rising towards daybreak to near 70°
Friday: There may be a brief scattered shower in the morning but otherwise partly cloudy, windy (gusts to 30 MPH) and warmer with muggy conditions…highs approach 85°. Storms are possible after 4PM as a cold front comes towards I-35.
Friday night: Storms with areas of heavy rain expanding in the region. Lows dropping through the 60s
Saturday: Off and on rain/drizzle and cooler with highs in the lower 70s
Sunday: We go back into the muggier weather again with perhaps a scattered storm. Highs 80-85°
There is a lot going on over the next week…and I don’t want to forget about the more substantial cold front likely sometime next Wednesday which will send our lows down considerably…and the highs too…later next week. More on that next week though.
Let’s start with the dew points this morning. It’s one of the big reasons why things feel so nice out there to start the day. Dew points are near 50° locally…but the following map shows the much higher dew points south of KC…towards OK/AR.
65°+ dew points south of the I-44 corridor…that’s important because while today the winds will be more from the SE…tonight the come around towards the south…so we end up with these dew points by mid day tomorrow.
Near to above 70° are the forecast dew points off the NAM model from earlier this morning).
In addition to the moisture at the surface…the atmosphere as a whole will be pretty saturated…
The map above shows the Precipitable Water or PW. The higher we go above 1″ the more moisture there is for whatever develops to turn into efficient rain producers. It’s not as high as the set-up last week (over 2″) but it’s pretty darn high for late September and it will be aligned with the front coming through the KC region later in the day. This means that as the storms form…they will be forming in an environment of juicy air not only at the surface but also above us as well.
By the way this “juicy” air stays with us for the entire weekend.
The front which will set everything into motion tomorrow late day/evening…doesn’t really exist yet…nor will it really till tonight. The colder air mass will develop in the northern Rockies and spill out through the northern Plains and then move southeastwards towards us tomorrow afternoon.
So that by 4PM Friday…surface temperatures will range from the 90s in the Plains to 50s in the northern Plains…
You can see the forecast temperature contrast across our area more clearly with this next map…
This is from the hi-res NAM that has the front through a bit quicker…
Notice northern MO…then the contrast towards Downtown KC and southwards.
All this should come together for storms later tomorrow.
There will be a cap that needs to be broken however…and that is certainly worth mentioning…for storms to fire along and ahead of the front. As a matter of fact this may be being underestimated right now in my opinion, at least for the potential of severe weather. IF that cap holds…the risk of severe storms may not come together in time.
Here is the severe weather risk via the SPC…
This seems about right to me…again that cap needs to be watched because IF the storms form behind the front…our severe weather risk would be lower in the KC and points north area.
Hail/winds are the two main threats if storms break through the cap
Storms that do form will do so with the front. The front is oriented from the NE to the SW…the storms will be moving from the SW to the NE and the front itself will only slowly move south of KC…this leads to training cells as a concern and with all the moisture in the atmosphere…remember the map I posted above…that means there should be some pretty heavy rainfall rates despite the fact the the individual cells will be moving along at a nice clip.
As a matter of fact IF this front doesn’t push too far southwards…we may see the front return northwards rather quickly on Saturday. That is both a good and bad thing. We get more unstable Saturday…and there is a wave coming out from the SW…that has to spell more rain and storms…
By the way…the wave coming out on Saturday…is the same upper level system that’s been spinning around Arizona for the last few days bring them all sorts of crazy (by Arizona standards) storms and flooding rains. That thing targets our area Saturday. The NAM model in particular is rather strong with this thing Saturday…
So at this point…have some plan Bs ready to go for Saturday…it may not rain all day…but it probably won’t be a pretty day.
I haven’t been able to get to a Royals game this year…I have tickets for Saturday night…so I do have an interest in getting some drier weather here in time.
Our feature photo comes from Debi Jordon Zink out in Grain Valley from earlier this month.