Tuesday, 11:45 a.m.
As we get ready to close the books on October, there is some cold air on the playing field, but what there is of it is not really enough to generate any meaningful snow. Instead, severe weather is much more likely over the next 48 hours.
A storm organizing over the eastern Rockies and western Plains tonight will head northeastward tomorrow across the central Plains. The air mass in the southern Plains and over the lower Mississippi Valley is plenty warm and moist. Dew point temperatures have climbed into the 50s across much of central and eastern Kansas and much of Missouri this morning, and into the 60s across much of Oklahoma and western Arkansas. That kind of moisture will be the fuel for some potent thunderstorms in the next 36 hours. Here's the overall setup:
Many severe weather parameters are in place, and with a pretty strong cold front coming out of the Rockies tomorrow and running into this warm, moist environment, chances are good there will be some strong thunderstorms around, and potentially severe thunderstorms.
As storms go, this is not going to be a powerful one. Indeed, if you look at the contrast in air masses Thursday evening from the warm side of the front attached to this storm to the cool side, it will end up not being all that great. Yet severe weather appears likely, along with flooding downpours. If you look at the upper-level setup, the area between the Plains and Mississippi Valley will be caught between a rock and a hard place:
That's the 500mb forecast for tomorrow night, and it shows the warm ridge over the eastern Gulf of Mexico and the upper-level trough coming through the Rockies and squeezing out that storm across the Plains toward the Midwest.
It will turn cooler behind the front, enough to erase the threat of severe weather, but the cooling will come in two stages. And the cooling won't be enough to generate much in the way of snow at week's end and into the weekend. In fact, snow will be lacking in general going into the first week of November across most of the country, and another front crossing the nation next week may also generate more severe weather.
Blocking over the Atlantic and in Europe is buckling the jet stream over the central and eastern U.S. to extend the cool and wet weather the rest of the week and into the weekend.
More excessive wetness is in store from the mid-Mississippi Valley to the mid-Atlantic states, while the brutal heat continues in the West and especially the Northwest this week.
A cool season storm will bring flooding rains and very cool air to the Ohio Valley and Northeast tomorrow into the weekend, while the Northwest has record-setting heat with sunshine.
As the jet stream undergoes amplification late this week into the weekend, it will lead to extremes of heat in the Northwest and cool and wet weather in the Ohio Valley, mid-Atlantic and parts of New England.
Heat and humidity surging across the Mississippi Valley will spark severe thunderstorms in the next 24 hours. The pattern will remain wet from the northern Plains to the East Coast for a while.