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In Brief:
An encroaching trough will hold off the heat wave this weekend. The moisture flow is also remaining fairly healthy - we see another chance of severe thunderstorms tonight (Friday). We dry out for the weekend but only hit the upper 90'sF on Sunday.
After that we slowly cool until a strong cold front brings in a taste of Fall at the end of next week and weekend.
Forecast Discussion:
The trough to our west is holding stronger than expected - this is keeping temperatures a bit cooler through Saturday than expected earlier in the week (Figure 1). We still have tropical moisture from the south and east and Pacific moisture from the west coming in at different levels (Figure 2).
The SPC has us on the very western edge of a Marginal Risk of severe weather (1 on a scale of 1-5) for hail and high winds (as usual).
2pm Friday Update:
The forecast for today going into the weekend is on track. The Marginal Risk (1 on a scale of 1-5) for severe weather (for hail and high winds this afternoon) has been nudged westward to include most of Longmont (Figure 1 update). The Slight Risk (2 on a scale of 1-5) is just a few miles further east. There is a chance for tornadoes in the middle of the Slight Risk region.
For Saturday - we warm up to around 90F and have almost no chance of a storm at all (dry air and lack of upper level support - Figure 2 update). The real heatwave (almost 100F) is still confined to Sunday only.
End 2pm Friday Update.
The Longer Range Forecast:
We hover just around 90'F Friday and Saturday then the ridge hits us hard for a day (see the ridge in Figure 5). We hover in the 80'sF through mid-week then a powerful cold front is still coming in Thursday PM. Highs in the lower 70'sF (or only upper 60'sF ?!) are possible on the Plains. Rain showers (not so thundery) are possible Thursday night into the weekend as well. Exciting!
