In Brief:
Normal summer weather sets in.
Friday Update:
We did see three tornadoes touch down yesterday, and lots of large hail. Severe weather shifts out to the eastern plains today. You should see a wall of big thunderstorms form to the east this afternoon. We return to seasonable temperatures (mid to low 80's) with a small chance of afternoon thunderstorms each day.
End Friday update.
Thur Update:
Yesterday was an active day. Longmont received, on average, another 1/2 inch of rainfall (more on the south side). There were 8 tornadoes reported in the state (Figure 2 update).
All the conditions are still in place for a repeat today BUT the risk of the more severe forms of weather, including tornadoes, includes areas west of I-25 and up into the foothills (just barely to Estes Park and including Red Feather Lakes, for example - Figure 3 update). Like yesterday, stay alert this afternoon and evening.
End Thur update.
Same day update:
Right after today's post went up, the Storm Prediction Center upped our risk for severe weather to Enhanced (3 on a scale of 1-5). There is a better chance of large damaging hail and tornadoes from west of I-25 to out on the eastern Plains (Figure 1 update). Be alert for severe thunderstorm and tornado watches and warnings that will be issued this afternoon. I don't post watches and warnings here (I'm not always online). Please use apps like weatherbug and storm shield to be alerted!
End same Forecast Discussion.
Substantial moisture has returned, and the jet stream is setting up to help all flavors of severe weather to occur near or along I-25 today and probably Thursday as well (Figure 1). Storms should begin to effect the foothills and I-25 communities between 1-2 p.m. both days. Precipitation chances remain elevated until around 10 p.m. - 12 a.m.
The foothills are covered by a marginal risk (1 on a scale of 1-5) while I-25 folks eastward have a slight chance (2 out of 5 - Figure 2). Hail, high winds, and even a few tornadoes are possible very close to Longmont and Broomfield and northward (Figure 3). Stay alert!
For Thursday, the slight risk pushes a bit further west. Hail and high winds are forecasted (Figure 4). Right now (Wednesday), there is no forecast for tornado chances, but that may get updated later tonight or tomorrow morning.
Rain, east of the Divide, may be very substantial in spots as well. Figure 5 shows widespread 1"+ totals raising flooding concerns since the region is still quite saturated from the season's excessive rain to date.
The Long Range forecast:
After these couple of days of excitement, we return to seasonable temperatures and small to zero rain chances (Figure 1).
