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Seasonable temperatures in the 80s continue this week with mostly dry weather expected.

Short Term

A ridge of high pressure in the Southwest US and a trough over the Great Lakes has led to a subsident upper level flow through our area. That promotes high pressure and dry weather. At the surface, broad high pressure extends from western Ontario south into northern Missouri this afternoon with this high gradually nudging east over the next couple days. Tonight we'll see winds go light and temperatures drop into the low 60s and upper 50s. For some this will be the first time we've seen 50s since June. Clouds have the potential to complicate the cooling forecast tonight, especially in central Missouri. A limited attempt at moisture return northward through the Plains tonight may trigger an area of convection in Nebraska, tracking southeast into western Missouri. The rain from this likely stays west of our forecast area, but clouds have a better potential to spread into central Missouri, potentially holding temperatures a bit warmer overnight, in the low 60s. Tomorrow will be a very similar day to today, though perhaps a few degrees warmer. The high slides east allowing winds to turn southeasterly. Another day of sun will help to modify the air mass back into the low to mid 80s.

Long Term

The trough in the east sees some reorientation this week. The initial trough lifts northeast out of New England and into the Canadian Maritimes while another trough arrives from the west and digs into the Great Lakes to replace it. Meanwhile, the Southwest Ridge remains largely in the same location with some daily wobbles. For us locally we'll maintain the persistent northwest flow aloft with richer moisture remaining suppressed to the south and west. Temperatures continue to gradually rebound through the mid and even upper 80s by Wednesday.

The next trough arriving in the Great Lakes pushes a cold front southward through our forecast area Wednesday into Wednesday night. This represents our next best chance for rain, but those chances remain fairly limited locally. The better forcing with the trough passes by to our north, while the richer moisture remains suppressed to our south. The low resolution ensemble (LREF) guidance remains more ambitious with rain chances than the the blend-of-models forecast. Of the LREF guidance, 60 to 70 percent of members produce rain across our forecast area in the 24 hours ending Wednesday night, up 10 percent from yesterday. Meanwhile, the blend-of-models forecast 12hour chance of rain remains in the 10 to 20 percent range. This discrepancy is partially a result of timing variance in the guidance, but also uncertainty in the development of another convective complex to our west over the Plains linking up with the better moisture. The LREF may also be overestimating the rain chances a bit due to the lower resolution of this guidance, something the blend-of-models forecast is tuned to adjust for with low expected rainfall events. If we look deeper in the LREF we see the percentage of members that produce 0.05 inch or greater rainfall is only 30 to 40 percent over that same time period. This gives credence to the idea that the low resolution guidance may be indicating more widespread light rain amounts than should be expected as precipitation in this time period should be convective in nature.

The air mass behind Wednesday's front is not as cool and dry as the last one, and we only get a small taste of it. So we do see the high temperature forecast for Thursday and Friday a few degrees lower than Wednesday, but still near normal for this time of year, in the mid 80s. Guidance is in good agreement that the western ridge flattens and spreads out across the southern tier of the country this weekend into the following week. This reduces the extremity of the heat within the ridge, but also broadens that warmth back into our area. By Saturday the the blend-of-models forecast probability of 90 degrees creeps back up into the 20 to 40 percent range. Mercifully, the humidity remains limited at least initially, with the blend-of-models forecast probability of 70 dewpoint only up to about 40 percent by the same time frame.