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The forecast discussion:
10:30am Update:
It looks like we'll have a nice round of storms roll through around 4-5pm today (figure 1 update). Nothing severe, but a few neighborhoods may pick up a quick heavy dump of moisture. Most folks won't see that much rain.
Figure 1 update: the HRRR reflectivity forecast for 4pm Saturday July 21 from weather5280.com
End Update 10:30am.
The heat is beginning to appear in our rear view mirror. As I write, on Friday afternoon, it has already climbed to 98°F. We should only get to 94°F today and 91°F Sunday. (That is 'some' relief.)
The ridge (Figure 1) is still overhead today- which explains the persistent heat. The next trough is still up in the Pacific Northwest.
On the western side of the ridge, some moisture is coming in. There is one river of moisture coming out of the Gulf of Mexico and one from the lower tropics up west of Mexico. Both are flowing into the Western U.S. (Figure 2).
The longer range forecast:
By Sunday AM the trough is slipping in and sending a cold front down into Colorado (Figure 3). It won't arrive until about 1pm. The high for the day will occur about noon to 1pm.
For Saturday PM there is a statewide chance of showers (Figure 4). Another peak chance of rain occurs after noon Sunday with a possible 1/4th inch of rain locally (Figure 5). This is less rain than earlier models predicted. The temperatures on Monday do drop to 79°F. (Tuesday we climb back to 89°F though...)
