Ron Chalfant, LakeGregoryWeather.com
Today’s lakegregoryweather.com
Forecast for Crestline, Twin Peaks, Lake Arrowhead and the San Bernardino Mountains:
04/28/2018.
Good Morning.
The Forecast for the next several days, is quite complicated. Today, an area of Low pressure that has been sitting off of the Northern California Coast has moved into the Great Basin. This Low will remain stationary over the Idaho, Utah, and Nevada today. Then, a compact Low will develop offshore of Washington State Monday. This system will merge with the system over Idaho Monday.
As this transition develops, the combined system will elongate toward SoCal spreading rain and snow along it’s path. Today as this pattern develops, the first of several waves will pass through SoCal, mid level moisture has moved from the San Diego area into the Inland Empire producing fog and low clouds all the way to our local Mountains below the 5500′ level. Locally, we should see some partial clearing today for the Crestline and Arrowhead areas. Big Bear, Running Springs, Arrowbear, and Green Valley Lake are all above the moisture and have humidity levels in the low 20s, while Sky Forest, Crestline, and the surrounding area have humidity levels around the 90% and above.
This is due to a temperature inversion at ~6000′ level and a fairly strong onshore surface pressure gradient of ~7.5mbs from San Diego to Tonopah. Later this evening, the Moisture will deepen across the area as the second wave moves closer to the area. Fog and low clouds will thicken by Monday morning, so expect to have a foggy commute in the morning. Gusty winds will be likely through the period from the South West. A WIND ADVISORY is in effect for the local area through 4am Monday. For gusty SW winds 10-25mph.
Now is when things get tricky. As the area of Low pressure moves into SoCal, Thunderstorms, Rain, with Snow possible above the 5500′ level at times, will be the Forecast through Wednesday Morning. Rainfall totals are expected to be in the .50-1.00″ range, and snowfall amounts at the higher elevations (~6000’+) is expected to range from 1-3″ possible through Wednesday morning.
Here is where the models break down, the Compact Low that will merge with the other system Monday, is looking like it will separate once again and set up off of Baja California Thursday. If this happens, we could see Tropical Moisture feed into SoCal for the latter part of the week. This could mean more warm showers and the possibility of T-Storms local especially in the Big Bear area. So overall, it looks like May will come in strong. That’s it for today. More on this tomorrow. Have a great Day, and enjoy the interesting Mountain Weather. RC
Temperatures around the area for Today and overnight:
Crestline, Twin Peaks, and Lake Arrowhead: 50-56*/ 34-40*
Running Springs, GVL, and Big Bear: 50-59*/30-35*
San Bernardino: 70-75*/48-55*
On another note, there is a new source for local news that can be found at, mountainreporter.com
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