Thursday, July 27, 2017
The Steamboat Springs area finally received some beneficial rainfall from one of Southwest U.S. Monsoon surges that have been passing through the last few weeks. Around a half inch of rainfall was recorded in several locations around the city from Tuesday night through Thursday afternoon, with the town waking up to a rare steady rain Wednesday morning.
Activity will decrease today, but rain chances increase again later on Friday as the northern California low pressure system talked about in the last forecast begins it’s eastward trek across the Great Basin. Some energy ejects out ahead of the storm and moves over our area later Friday, increasing chances of rainfall Friday afternoon and evening.
After the ejecting wave passes, the northern California storm moves bodily into the Great Basin on Saturday, pushing the ridge of high pressure over the western states eastward. Another monsoonal surge appears on the the western periphery of the ridge, and embedded sub-tropical waves will once again increase the chances for locally heavy rainfall Saturday afternoon and evening.
Model disagreement makes Sunday’s forecast uncertain with the northern extent of the sub-tropical moisture battled by some dry air to our north. There could be another chance of locally heavy rain on Sunday or it could be drier than Saturday.
By Monday, there is model agreement that another robust surge of monsoon moisture and energy will begin and last through Tuesday. If the energy moves as far north as currently forecast, Steamboat Springs has a good chance of locally heavy rain for both days.
Longer range models have the western ridge retreating back westward as energy over the eastern two thirds of the country interrupts and reverses the eastward progress of the ridge. Much drier air is advertised for the rest of the work week and heading into the following weekend. This may spell the end of our monsoon season as the two week forecast has the strengthening westerlies of our next season moving southward. If this occurs, it will suppress any northward moving moisture and energy from the southern latitudes to our south.