Fair and warmer the next two days then the last Storm of April to roll in Friday AM…..Although it will be a cold opener….Warmer weather is on the way beginning Sunday then well into Tuesday…….
Wednesday April 23, 2014
Posted at 9:30 am by Howard
Wednesday PM Update:
there are a lot of opinions several of the Dweebs out there, including forecasters’ from the east coast to the west on what this storm is going to do. The QPF from HPC is deafening with amounts suggestive of 2.4 inches which is pretty amazing but not unusual for the Fishing Opener Weekend.
I just spoke with the lead forecaster at WSFO RNO this afternoon and he was definitely a dry foot compared to HPC, giving the Sierra about a foot over the crest for the Friday-Saturday period. The emphasis is on late Friday afternoon and evening.
Here is a copy of HPC discussion of a wet foot perspective….
THE START OF A RATHER UNSETTLED FEW DAYS ACROSS THE WEST… AS PAC DYNAMICS WHICH WILL ARRIVE INTO THE PAC NW ON THURS IS FOLLOWED BY A RATHER POTENT DIGGING UPPER JET TO HELP ESTABLISH A RATHER AMPLIFIED UPPER TROUGH AXIS ALONG THE ENTIRE WEST COAST ON FRI WITH THE SRN STREAM TAKING OVER ON SAT AS A DYNAMIC UPPER TROUGH WITH SLIGHT NEG TILT ROLLS INTO THE DESERT SW. ON FRI… LOWERING UPPER HEIGHTS WILL CRASH DOWN THE WEST COAST AND GRADUALLY TAP INTO A PLUME OF ANOMALOUS PAC MOISTURE CONTENT… 850-700MB MOISTURE FLUX ANOMALIES 2 TO 3 TIMES ABOVE AVG… FOR WIDESPREAD QPF. THE MAIN FOCUS OCCURRING ACROSS NRN/CENTRAL CA AND SIERRA INTO A LARGE PORTION OF THE INTER-MOUNTAIN WEST FROM NV TO ID. THEN ON SAT… THE IMPRESSIVE UPPER JET DRIVES THE SHORT WAVE TROUGH AND DEVELOPING CLOSED MID-LEVEL LOW THROUGH SRN CA AND INTO THE WRN EDGE OF THE FOUR CORNERS REGION. ITS THIS DAY… WHERE A LONG FETCH OF HEALTHY PAC MOISTURE INTERACTS WITH SUBTROPICAL JET DYNAMICS FOR WIDESPREAD QPF ACROSS MUCH OF THE WRN STATES. ECMWF 850-700MB MOISTURE FLUX ANOMALIES BECOME OFF THE CHARTS GENERALLY RANGING FROM 4 TO 5 TIMES ABOVE AVG. THUS EXPECT QPF FROM CENTRAL/SRN CA AND AZ NORTHWARD THROUGH THE INTER-MOUNTAIN WEST INTO THE NRN ROCKIES/PLAINS. WPC GENERALLY FOLLOWED A BLEND/COMPROMISE OF THE ECMWF/UKMET WITH THE INTERNAL PSEUDO BIAS CORRECTED GUIDANCE BOTH DAYS WITH ASSISTANCE FROM PRISM DATA TO HIGHLIGHT THE FAVORED WRN TERRAIN.
Models continue to flip-flop with now the EC showing more of a split on last nights 00Z run while the 06z GFS was better in a more progressive solution. New 12z GFS out through 96 hours is very encouraging with QPF amounts in the 1.00 to 1.5 range for the Sierra South of Tahoe. If the ECMWF in its 12z Wednesday run is in line with the GFS then will be in a higher confidence situation.
The Dweebs understand that we are right in the mists of transition season and the models do not handle storms of this nature very well. However, this will be a cold storm with -8C at 700MB down here Saturday AM and the fishing opener is going to be cold with possible mid to upper teens for the opener over Long Valley at day break….so dress warmly. High temps will climb into the low 50s during the day Saturday, and Sunday will be warmer, then substantially warmer Monday and Tuesday.
The Dweebs are still sticking with a good 12 inches to as high as 18 inches over the upper elevations by Saturday AM….. This is a difficult storm to forecast QPF wise because of how late it is coming in……
Will Update the QPF time permitting this afternoon….
The MJO is forecasted to move into phases spaces 8-1 during the week two period. This is usually highlighted by a Cold East and a warm west. If you look at the analog’s for the past couple of discussions you will see why.
It is what happens after phases 8-1, which gets us into weeks late 2 and 3 where the Air Sea Coupled CFS may be hinting at. I have seen plenty of Mays living here in Mammoth for over 35 years with generous snowfalls for the upper elevation while the town gets little. For you die hard skiers and borders, after this weekend there may still be another one or two snow producing systems in May!