Remnant’s of Dolores’ is over the Sierra Today…..Very light upper flow combined with high instability indices will increase the possibility for heavy down pours in many areas today for Mono County….Main action will shift off to areas east of Highway 395 by Wednesday afternoon as an Upper Trof with Drier Air approaches…..This up coming weekend will be Fair…Dry and Warm………
Tuesday July 21, 2015
Posted at 8:30 am by Howard
Today Tuesday appears to be potentially the most active day for thunderstorm’s with heavy downpours. This mornings sounding showed a weaker inversion above 16,000 feet than what was the case yesterday. This means that there is a weaker warm air pocket in that area causing the Cap to the lift yesterday. Additionally…..increased moisture from the remains of Dolores’ and a CAPE of close to 1,000 J/KG and lifted’s -3 to -5 will be more than enough over the higher elevated heat source of the Sierra to punch through that weak inversion.
The NWS-RNO has issued a flash flood watch for Mono County from 12:00pm Tuesday to 8:00pm Tuesday night, for the potential for heavy rain downpours in showers, and flash flooding in areas that are susceptible. If you are traveling over local mountain passes be careful of falling rocks on to highways and if fishing in areas of Creeks and Streams during heavy rain storms today, move to high ground. Highs today will be near 70, lows near 50.
As an upper trof with drier air begins to approach later Wednesday, thunderstorms will form over the sierra in the morning and push-off to areas east of highway 395 during the afternoon. So there is the threat of more rain Wednesday but it will be mostly east of the sierra crest by afternoon. High temps will be a little warmer Wednesday afternoon. Afternoon and evening SW winds will increase.
By Thursday, the threat of rain should be all confined to areas east of highway 395. The upper trof pushing in will continue the southwest winds over the upper elevations and continue the drying process. Breezy weather is likely Thursday with warmer temps Friday. Highs will climb back into the low 70s, with over night lows in the upper 30s and 40s.
This weekend’s outlook will be fair, dry and warm with highs in the mid 70s at resort levels and nighttime lows in the 40s. Expect the usual light diurnal afternoon zephyr winds…
Longer Range……Always subject to change…….:-)
OK…. where are we headed the next week in this unusual El Nino Summer!
As we wrap up the weekend….The beginning of the last week of July looks pretty uneventful. Somewhat season temps can be expected with fair skies. So High temps will probably remain in the low to mid 70s with lows in the 40s, pretty much like the weekend. With that said, the second half of the week will be different. Looking at both the Ensembles of the GFS….and Ecmwf from last night, The GFS shows a somewhat progressive pattern with initially the Continental High over the SW expanding westward with a warm up Wednesday into Friday then it progressing east over that weekend.
The net result would be a stronger zephyr over the Bluesa weekend with daytime highs in the upper 70s. However the ECMWF has a different scenario. It retrogrades the desert upper high over CA and brings on a heat wave with highs in the 80s for Mammoth. Not too shabby for the beer drinkers Saturday afternoon. The nights would be warmer too with low 70s continuing possibly until nearly 8:00PM with very light of any winds. Thunderstorm action would not be likely.
At the moment, I do not have a bias either way. I do not see a reason why the EC is retrograding the mid level pattern. One interesting feature is that the MJO has moved in over the Indian Ocean. That can cause some retrogression, however the dynamic models are not picking up on that. Only for some reason, they show an incursion into phase space 1-2 which is not connected to the MJO. Some of the dynamic models are possibly picking up on a lower frequency signal like an atmospheric Kelvin Wave. Will update tomorrow AM after the CPC briefing today on this curiosity.
Either way the weather looks great at this point in time for the Mammoth Festival of Beers and Bluesapalooza, with either seasonally warm temps in the upper 70s with afternoon breezes or it will be well above normal in temps with highs in the mid 80s with out much of any breeze.
Tuesday 12:00 UPDATE:
Just had a look at the new high Res deterministic GFS 12Z Tuesday Run. It looks like the ECMWF Ensembles….so its leaning toward the hotter end of the month scenario. The big question will be is there is going to be SE flow up the CA/NV Spine? Too soon to tell….
5:10 PM Tuesday Update:
OK…here we go again! dé·jà vu to last June. The deterministic runs and ensembles are trending to a similar pattern in June with 597 MB heights over Nevada with SE flow following. This is where we got the hottest temps of the Summer in mid to late June followed by a Thunderstorm break out prior to the Fourth of July. The Dweebs just hope the rains hold off until after the Bluesapalooza.
Dr Howard and the Dweebs………………………………..:-)