106
FXUS65 KSLC 270938
AFDSLC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
338 AM MDT TUE OCT 27 2020
SYNOPSIS
HIGH PRESSURE ALOFT CENTERED NEAR THE WEST COAST
WILL LEAVE UTAH UNDER A DRY AND STABLE NORTH TO NORTHWEST FLOW
ALOFT THROUGH MIDWEEK. A GRADUAL WARMING TREND WILL ENSUE, WITH
TEMPERATURES RETURNING TO TYPICAL LATE OCTOBER READINGS LATE IN
THE WEEK.
SHORT TERM (THROUGH 12Z FRIDAY)
A LARGE SCALE OMEGA BLOCK
EXTENDS ACROSS THE EASTERN PACIFIC/WESTERN CONUS EARLY THIS
MORNING, WITH THE DOWNSTREAM UPPER LOW SPINNING OVER SOUTHERN
ARIZONA, AND THE UPPER RIDGE CENTERED OFF THE PACIFIC COAST.
THIS IS MAINTAINING A VERY COOL AND DRY AIRMASS ACROSS THE
FORECAST AREA, WHERE TEMPERATURES WILL MODERATE A BIT TODAY, BUT
REMAIN WELL BELOW CLIMO AREA-WIDE. GUSTY NORTH TO NORTHEAST WINDS
WILL CONTINUE ACROSS SOUTHERN UTAH, BUT SHOULD BE WEAKER THAN WHAT
WAS OBSERVED MONDAY.
THE BLOCKING PATTERN WILL GRADUALLY BREAK DOWN THROUGH MIDWEEK AS
THE UPSTREAM RIDGE VERY SLOWLY SHIFTS EASTWARD TOWARD THE PACIFIC
COAST, WHILE THE UPPER LOW SLOWLY TRANSLATES EASTWARD TOWARD THE
SOUTHERN PLAINS BY WEDNESDAY. THIS WILL ALLOW FOR A GRADUAL
WARMING TREND WEDNESDAY INTO THURSDAY, HOWEVER A REDUCED SUN ANGLE
AND COLD AMBIENT AIRMASS WILL LIKELY TAPER THIS WARMING TREND A
BIT ACROSS THE VALLEYS, AND HAVE LEANED TOWARD THE LOWER END OF
THE GUIDANCE ENVELOPE FOR TEMPERATURES, WHICH SHOULD FINALLY
RETURN TO NEAR CLIMO BY THURSDAY.
LONG TERM (AFTER 12Z FRIDAY)
RIDGING BUILDING IN FROM THE WEST
BEHIND THE SAME TROUGH THAT PROVIDED WINTRY WEATHER AND COLD
TEMPERATURES LOCALLY HAS TRENDED STRONGER AMONG RECENT MODEL RUNS.
A DRY WEATHER STRETCH IS ANTICIPATED, WITH WARMING CONTINUING
EACH DAY THROUGH AT LEAST SATURDAY. AS THE RIDGE ESTABLISHES
ITSELF OVER THE GREAT BASIN, GUIDANCE SHOWS 700 MB TEMPERATURES
CONSISTENTLY IN THE 5-7 DEGREE C RANGE. WE CAN EXPECT TEMPERATURES
AROUND 5-10 DEGREES WARMER THAN CLIMO FOR UTAH AND SOUTHWEST
WYOMING FOR THE START OF NEXT MONTH. THAT RIDGE IN PLACE WILL
RESULT IN MORE CONSISTENCY IN TEMPERATURES AS WELL.
ADJUSTED HIGH TEMPERATURES SUNDAY AND MONDAY UP SLIGHTLY FROM
NBM, AS IT HASN'T SHOWED ENOUGH INCREASE AFTER RIDGING SETTLES IN.
OVERNIGHT INVERSIONS COULD LIMIT AFTERNOON TEMPERATURES, AND
ADDED MIXING WILL ELIMINATE THOSE QUICKER. THAT WILL ALSO PLAY A
ROLE IN THE TEMPERATURE FORECAST.
AVIATION
VFR CONDITIONS ARE EXPECTED AT KSLC THROUGH THE VALID
TAF PERIOD. SOUTHEAST WINDS WILL TRANSITION TO THE NORTHWEST
AROUND 19Z WITH CLEAR SKIES. NORTHWEST WINDS WILL TRANSITION TO
SOUTHEAST AGAIN AROUND 03Z WITH A FEW HIGH CLOUDS.
FIRE WEATHER
A COOL AND DRY AIRMASS WILL REMAIN IN PLACE
ACROSS THE REGION TODAY, TO THE NORTH OF A LOW PRESSURE SYSTEM
SPINNING OVER THE DESERT SOUTHWEST. GUSTY NORTH TO NORTHEAST WINDS
WILL PERSIST ACROSS SOUTHERN UTAH AGAIN TODAY, WHILE HIGH
PRESSURE BEGINS TO BUILD ACROSS NORTHERN UTAH. THIS HIGH WILL
BECOME THE DOMINANT WEATHER FEATURE THROUGH THE REMAINDER OF THE
WEEK MAINTAINING DRY WEATHER AREA-WIDE. TEMPERATURES WILL SLOWLY
WARM THROUGH THE WEEK, RETURNING TO NEAR NORMAL BY THURSDAY THEN
WARMING ABOVE NORMAL HEADING INTO THE UPCOMING WEEKEND.
SLC WATCHES/WARNINGS/ADVISORIES
UT...NONE.
WY...NONE.
SEAMAN/WILSON
FOR MORE INFORMATION FROM NOAA'S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page