This will be a brief post as this weather situation may change some over the next few days.
Synopsis: The weather looks quiet for the next few days in Carson City and the eastern Sierra, then a rather strong storm system for this time of year will affect the area late in the week.
Looking at the latest forecast simulations, a moderate to strong atmospheric river event is becoming likely for the end of the week. The remains of former super typhoon Jelawat and additional energy from the subtropical jet are moving toward the west coast at this time. The time of arrival for the moist plume is expected to be around late Friday night into Saturday for the heaviest rain and snow. Current IVT values suggest that the incoming system will have significant moisture available as shown with the below animation and IVT values.
The first round of rain will likely begin late Thursday night into Friday afternoon with decent isentropic lift.
The main event at this time looks to arrive late Friday night into Saturday. This period brings the potential for the heaviest rain and high elevation snows to the area. The GFS and ECWMF operational runs and most ensembles are both in fair agreement that 2-4 inches of precipitation will fall along the Sierra crest with amounts tapering to around 1 inch to 1 ½ inches along the Sierra front and portions of western Nevada. There are some differences whether north or south for the focus of the heaviest precipitation. With the high snow levels, hydrological concerns for area creeks, streams and rivers may arise as a result of the expected heavy precipitation with high snow levels.
At this time, it’s difficult to determine how much precipitation will fall, but this storm has the potential to bring very heavy rain and high elevation snows to the area. Stay tuned and keep any flood mitigations in check for the next 6-10 days.
Looking ahead, a ridge looks to build in for Sunday into Monday, but the active weather may continue with colder systems likely into the following week.
Stay Tuned as the weather looks to become more active over the next couple of weeks!