####018003840####
AGUS76 KRSA 251550

HMDRSA



Hydrometeorological Discussion

National Weather Service / California Nevada RFC / Sacramento CA

830 AM PDT Thu Apr 25 2024



...COOL WITH PERIODS OF SHOWERS AND ISOLATED THUNDERSTORMS POSSIBLE, 

ESPECIALLY OVER THE HIGHER TERRAIN THROUGH FRIDAY... 



...MAINLY DRY AND WARMER OVER THE WEEKEND INTO TUESDAY...



.METEOROLOGICAL CONDITIONS (THU AM - WED AM)...



Upper level trough continues to move east into the four corners 

region this morning as another shortwave trough and associated front 

approach the Pac NW and Nrn Ca coast.  The trough deepens over the 

region this afternoon into Friday. Two main areas of showers this 

morning with one ahead of the front and shortwave trough along the 

NW CA coast and into Srn Oregon and another group over North Central 

NV. Also, a few showers over Srn Ca and Srn NV with light rain. 

Showers will increase over Srn OR and Nrn CA (mainly along the coast 

and higher terrain) and into NE NV during the day into tonight. Best 

chance of thunderstorms is over Eastern NV today. Precip amounts 

will be variable due to convective nature of showers. Precip amounts 

generally around 0.75-1.25 over far NW CA coast and west slope of 

the Srn OR Cascades and around 0.25-0.75 inches over Nrn NV and 0.1-

0.5 inches over the Nrn Sierra and generally a tenth of inch or less 

along the CA coast and over Srn Sierra and Srn NV and Srn Ca 

mountains. Precip amounts for Friday generally around a quarter of 

an inch or less except locally to around a half an inch mainly in 

the Nrn Mtns including the Srn OR Cascades and Ruby Mtns and along 

the NW CA coast and along the Sierra. Precipitation stretches south 

along the Sierra and into Srn NV and possible a few showers over the 

transverse mtns and into San Diego County Mtns Friday. Thunderstorms 

possible over the Sacramento Valley and Shasta region and alog the 

Sierra and east over Nevada. The trough shifts to the east Friday 

night into the weekend with weak ridging over the region and 

shortwaves to the north approaching the B.C./ Pac NW coast. This 

will bring warmer and mainly dry conditions to the region except 

some light precip possible over the far NW CA coast and west slope 

of Srn OR Cascades over the weekend. More of the ensemble members 

and deterministic GFS and EC keeping the shortwaves farther north 

than yesterdays runs. Although there are a few GFS and EC members 

(16% of total members, 27% GFS and 16% EC) that show a deeper trough 

into the northern part of the region starting Tuesday with others 

delaying it into Wednesday or Thursday. 



Max temperatures near normal to 15 degrees below normal across the 

region this afternoon and similar Friday afternoon. Temperatures 

warm up to near normal for most of the region except around 10 

degrees below normal along NW CA coast Sunday afternoon and warming 

to near normal to 10 degrees above normal over the region on 

Tuesday. Overnight temperatures near normal to around 10 degrees 

above normal tonight decrease to around normal Friday night then 

warming to near normal to 10 degrees above normal Sunday night 

and above normal up to 15 degrees Tuesday night. 



Freezing levels around 5000-7000 ft over Nrn CA and 8000-10000 ft 

for Central and Srn CA and NV this morning and around 4000-6000 ft 

over Nrn CA and 6000-8000 ft elsewhere Friday and rising to around 

6000-8000ft over Nrn CA and 8000 ft and higher elsewhere Saturday 

and 4000-6000ft over far NW CA coast and Srn OR and 7000 ft and 

higher for the rest of the region Sunday into Monday and rising to 

8000 ft and higher across the region Tuesday.





QPF graphics are available at www.cnrfc.noaa.gov/qpf.php







Osborne



$$