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AREA FORECAST DISCUSSION

 
 FXUS65 KSLC 262156
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
356 PM MDT THU MAR 26 2015

.SYNOPSIS...HIGH PRESSURE WILL BRING A WARMING TREND TO THE REGION
INTO THE UPCOMING WEEKEND...FOLLOWED BY A SLIGHT COOL DOWN SUNDAY
INTO EARLY NEXT WEEK.

&&

.SHORT TERM (THROUGH 12Z MONDAY)...STRONG MID LEVEL RIDGING ALONG
THE WEST COAST WILL SLOWLY BUILD EASTWARD ACROSS THE GREAT BASIN
DURING THE DAY FRIDAY...RESULTING IN A WARMING TREND REGIONWIDE
WITH TEMPERATURES EXPECTED TO RUN MORE THAN 10 DEGREES ABOVE
CLIMO.

THE MODELS CONTINUE TO DISAGREE WITH THE EVOLUTION OF A
PROGRESSIVE SHORTWAVE TROUGH WHICH IS FORECAST TO CROSS THE
PACIFIC NORTHWEST/NORTHERN ROCKIES REGION SATURDAY. THE EC
REMAINS DEEPER AND MORE CONSOLIDATED WITH THIS FEATURE...PUSHING
A STRONGER COLD FRONT THROUGH THE FORECAST AREA SATURDAY AFTERNOON
THROUGH SATURDAY NIGHT. THE GFS MEANWHILE OFFERS A MORE SPLITTY
SOLUTION...AND STALLS THIS FRONT ACROSS CENTRAL UT SATURDAY
NIGHT...PROVIDING A FOCUS FOR ISOLATED SHOWERS/THUNDERSTORMS INTO
THE DAY SUNDAY.

CONFIDENCE IS LOW IN WITH RESPECT TO FAVORING ONE SOLUTION OVER
ANOTHER...AND AS SUCH HAVE MAINTAINED THE GOING IDEA OF ISOLATED
CONVECTION ACROSS THE HIGHER TERRAIN SATURDAY AFTERNOON INTO
SATURDAY EVENING WITH THE INITIAL FRONTAL PASSAGE...WITH ANOTHER
ROUND OF ISOLATED CONVECTION SUNDAY IN RESPECT TO THE GFS
SOLUTION.

&&

.LONG TERM (AFTER 12Z MONDAY)...LONG TERM FORECAST CONTINUES TO BE
RIFE WITH MODEL TO MODEL AND RUN TO RUN CONSISTENCY ISSUES. THE 12Z
GFS AND 12Z EC CONTINUE TO DEPICT DIVERGENT SOLUTIONS...WITH THE 12Z
EC CONTINUING TO THE TREND TOWARD A PROGRESSIVE TROUGH CLEARING THE
CWA WELL IN ADVANCE OF THE LONG TERM PORTION OF THE FORECAST.

THE 12Z GFS ON THE OTHER HAND...CONTINUES WITH A STRONGER SOUTHERN
SPLIT OF THE WEEKEND TROUGH...WHICH CUTS OFF NEAR SOUTHERN
CALIFORNIA...KEEPING A DEFORMATION AXIS ACROSS PORTIONS OF UTAH
MONDAY. THE MAIN DIFFERENCE FOR THE SENSIBLE WEATHER ACROSS THE
STATE WOULD BE THE CHANCE OF PRECIPITATION ACROSS THE AREA WITH THE
GFS SOLUTION. KEPT LOW END POPS IN THE FORECAST AS A BLEND OF THE
TWO SOLUTIONS.

HIGH PRESSURE IS THEN EXPECTED TO BUILD INTO THE AREA THROUGH EARLY
TUESDAY. ANOTHER STRONGER SHORTWAVE WILL CROSS THE NORTHERN ROCKIES
ON TUESDAY...BRINGING A COLD FRONT THROUGH THE STATE TUESDAY
AFTERNOON AND EVENING. AGAIN...THE GLOBAL MODELS ARE QUITE DIFFERENT
WITH THE GFS BRINGING A MUCH MORE DYNAMIC FRONT THROUGH THE CWA
ACCOMPANIED BY PRECIPITATION...WHILE THE EC IS LARGELY A DRY COLD
FRONT. AGAIN KEPT LOW END POPS IN AS A BLEND OF THE TWO SOLUTIONS.

TOWARD NEXT WEEKEND...THE EC DEVELOPS A FAIRLY ROBUST PACIFIC SYSTEM
ACROSS THE WEST...BRINGING A STRONG COLD FRONT AND ASSOCIATED
PRECIPITATION THROUGH THE STATE. THE GFS...ON THE OTHER HAND HAS A
FAIRLY WEAK...SPLITTING TROUGH ACROSS THE AREA.

GIVEN THE MODEL DISCREPANCIES...CONFIDENCE IN THE LONG TERM FORECAST
IS LOWER THAN NORMAL.

&&

.AVIATION...NORTH TO NORTHWEST WINDS AT THE SLC TERMINAL WILL SHIFT
TO THE SOUTHEAST BETWEEN 03-05Z.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...NONE.
WY...NONE.
&&




SEAMAN/KRUSE

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)