Moisture Fetch now lifting north with Some Sunshine expected today….Warming trend to kick into high gear Wednesday with upper 80s expected by Sunday in Mammoth…Heat wave may last 7 to 10 days…..High based thunderstorms a good possibility next week….
Tuesday June 25, 2013
Posted at 10:02 am by Howard
Moisture band still effecting the high country of the Central Sierra. Light rain fell Monday with amounts .12 to .15 recorded from RAWS sites around town. Checking SFO Radar, most of the shower activity is Sonora Pass north at the moment. Although there are still some showers to the west of Mammoth and out over the Valley. The latest guidance shows the upper jet along the CA/OR border today…then lifting NE toward Washington state and Canada Wednesday into Thursday.
Strong rapid height rises are expected at 500MB over the far west next 24 hours including Mono County. This mornings 12Z WRF shows the 588DM height line pushing north of Mammoth tomorrow morning about 8:00am. So although high temperatures will again be difficult to forecast today because of Cloud Cover, with the projected height rises, the moisture band should gradually move north today as well. So some sunshine is possible today and thus high temps will likely get into the 60s this afternoon.
The Dweebs did some MJO work and noted that for the months of June, July and August, when the MJO projects into the Wheeler Phase Space 1 and 2, hot weather can be expected for California. I think that the ECMWF Ensembles have a better handle on this, as it holds on to the heat longer. If the EMON is correct in its projection, we can expect very warm weather to develop as progged by both the GFS and EC beginning this Thursday. However, the EC 00z Tuesday continues the anomalous heat longer through the 360-Hours. The GFS on the other hand weakens the upper ridge too quickly after the 3rd of July. There is better support for the upper ridge to remain longer as the MJO remains in phase space 2 through about the 8th or 9th of July. See: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/EMON_phase_51m_full.gif
Thereafter the EMON tracks the MJO into phase space 3 which is cooler then normal for California. See: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/Composites/Temperature/JJA/combined_image.png
Thus the GFS may be much too quick in breaking down the upper ridge over the west. The EMON is suggesting that the heat will not break until about the 9th of July! For our high country, should this heat wave develop as planned, no doubt that eventually, air mass modification will give Mammoth a nice break with afternoon and evening thunderstorms while the Owens Valley Bakes into the 2nd week of July.
With the upper high again forecasted to be closer to California, record or near records are possible. Here are your record highs for the Owens Valley next week.
Sunday the 30th, 108; Monday 105; Tuesday 105; Wednesday 107; Thursday 107; Friday 108.
Dr Howard and the Dweebs……………………………:-)
Monday June 24, 2013
Posted at 10:01 am by Howard
Monday AM UPDATE:
Just a quick update…..The band of moisture currently headed into the Sierra still has the potential to bring some light rain or sprinkles today. The Dweebs are not expecting a lot but enough to possibly dampen the ground. The most notable change to the forecast is that temperatures will be quite a bit cooler than forecasted today. Highs will only get into the 50s today…some 20 degrees below normal. Night time lows will remain above freezing but into the upper 30s/low 40s. Feels a little like fall! Expect periods of gusty winds up to 35 MPH with ridge tope gusts to 60MPH. It will be another cool day on Tuesday. However not as cool as today….expect highs in the 60s. Some scattered showers are certainly possible Tuesday. Wednesdays weather is still looking good with highs in the 70s. Very warm weather is expected over the weekend with highs in the 80s. The only other adjustment to the forecast is that most of the modeling is keeping the upper high east enough for very warm temps…..however, no records if the trend continues. There are more then enough ensemble members keeping the upper high between the 4 corners states and Southern NV. Vegas may break some records but Bishop may be just plain hot without record heat. The location and strength of the upper subtropical continental high is what the Dweebs will be most focused on the next 5 days along with the possibility of Thunderstorms next week. More later this week on the developing heat wave and its effects upon the Eastern Serra. Dr Howard and the Dweebs…………………..:-)
Changable Weather Pattern over the Next Week with some light rain possible Monday/Night then very warm second half of Next Week
Friday June 21, 2013
Posted at 9:23 am by Howard
Sunday AM Update:
Increasing clouds are expected today with gusty SW breezes this afternoon and evening to 30 MPH. The first of 3 surges of moisture is now into Northern California. This will be mostly high clouds for our local high country. No precipitation is expected in Mammoth today. Expect highs a little cooler today in the upper 60s.
The 2nd surge will move into our area mid to late morning Monday. That appears to be the best surge associated with the best Upper Jet support. The jet axis is more like Eureka, Ca….SE through Tahoe with Mammoth to the South. This means that Mammoth is on the southern fringe of the storm track. Nevertheless, we may get a .10 of an inch or so of rain. The freezing level is at 12,500 Monday…..well above all high elevation mountain passes. Monday noon through Monday night looks to be the best chance of some light rain in Mammoth…….Great for the Motocross Track! The upper jet lifts north Tuesday, so any shower activity will be mostly in the Morning…
The further outlook still looks very warm. A continental upper high builds NW from out of Old Mexico. High temps in Mammoth will climb well into the 80s by Friday and stay there through the Fourth of July and possibly through that following weekend. I will update later on any Thunderstorm pattern that may follow…..as these type of heat waves normally are followed by a good TSRW breakout when the heights begin to fall. In the meantime, enjoy the comfortable weather that you are experiencing as it will be uncomfortable next weekend through much of the following week. Bishop could still see high temps hitting 100 by this Wednesday, 105 to 106 next weekend and if heights get close to the Magic 600Dm with 500dm-1000dm thick in the low 590s as forecasted by the new 18Z GFS today….high temps may be in the 107 to 108 range early that following week. Either way…you folks in the Owens Valley need to make sure your Swamp Coolers are maintained and operational……Later this up coming week through the Forth of July!!
Dr Howard and the Dweebs………………………….:-)
While today Friday looks pretty nice for the 1st day of Summer, there will be one last precip producing weather system from the Gulf of AK that may bring measurable precipitation to the Eastern Sierra, Sunday into Monday. Any Gulf of AK storm that brings precipitation to our area this late in June is unusual….but not unprecedented. This one is no exception as it has quite the moisture tap as it drags moisture from north of the Hawaiian islands into our area mainly Monday. By Tuesday it moves out with improving weather expected by the afternoon.
The Next big change in the pattern occurs about the middle of next week as the long wave trof off the pacific NW retrogrades and a strong Continental High establishes itself over the Great Basin and into intermountain west by next weekend. This is our warmest pattern here in the high country. And, being that it is occurring in late June, it is not likely to be accompanied by any Major Monsoon Flow to cool us off much. It is possible that Mammoth could hit 90 degrees by the end of next weekend with Bishop 105 to 110…depending upon exactly where the upper high sets up. The looks to be a protracted warm spell with highs of 100 beginning about next Thursday and continuing through the forth of July…. No doubt there will be Thunderstorms associated with this pattern on the back end>>>>>
More later on the high country heat wave that is ahead for us for later next week…..
Dr Howard and the Dweebs……………………….:-)