Showers and Thunderstorms Possible Tonight?


After a shaky night last night, the weather has been quiet, hazy and a bit muggy today. 

Humidity levels have raised the dewpoint into the low-mid 60s throughout most of the Coachella Valley at times today. We are experiencing a brief period of southeast flow, as a high pressure over NW New Mexico circulates a more humid and hazy airmass up from the southeast today. A small low pressure disturbance is caught up in this flow, and is currently near Yuma, moving northwest around 30mph. This small disturbance will move into the deserts this evening, and will combine with a low pressure moving east from off the coast of Baja. The interaction of the two systems will cause a convergence of southeasterly and southerly winds over Southern California. This is how the satellite looked earlier this afternoon.

For this evening, as mentioned in my previous report, there is a slight chance of a brief shower or thunderstorm (less than 20% chance) this evening and into tonight. Most areas will remain dry, but sprinkles, erratic winds and even lightning could possibly occur between about 5:00 tonight and through Saturday morning. Any outflows from thunderstorms could create brief blowing dust. Southeast winds will likely increase to 15-30 mph after about 5:00-6:00pm, especially east valley areas. Visibility may be reduced to 5-10 miles this evening, as large areas of 30-35 mph gusts over the deserts near Yuma will move dusty and muggy air northwest over our area.

As of 4:30pm, here is the current National Service radar showing the small circulation moving northwest from Arizona.

Small circulation east of Yuma will bring a slight chance of a shower or storm this evening as it moves across our area.

Small circulation east of Yuma will bring a slight chance of a shower or storm this evening as it moves across our area.

In the meantime, here's a graph showing how dewpoints have shot up into the 60's today at PSP, indicating raised humidity levels. A dewpoint temperature over 60 degrees makes evaporative coolers (i.e. swamp coolers) function less effectively, and makes the heat less tolerable.

I'll send out another update if storms develop more aggressively than currently predicted.

By Sunday, skies should be clear with more traditional windy conditions plaguing the normally windy locations along I-10 and on the north end of valley communities in the afternoon and evening hours early next week. Temps are expected to slowly climb toward the end of next week.