105
FXUS66 KSGX 131042
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
242 AM PST FRI FEB 13 2026
SYNOPSIS
SLIGHT CHANCE OF SHOWERS OVER THE MOUNTAINS TODAY. OTHERWISE DRIER
AND WARMER THROUGH SATURDAY. COOLER AND BREEZY SUNDAY. A WINTER
STORM WILL BRING MODERATE TO HEAVY RAIN, MOUNTAIN SNOW, AND GUSTY
WINDS MONDAY AND TUESDAY ALONG WITH A SLIGHT CHANCE FOR
THUNDERSTORMS. SNOW LEVELS FALL THROUGH WEDNESDAY, WITH ELEVATIONS
ABOVE 5000-6000 FEET LIKELY TO SEE HEAVY SNOW AND SIGNIFICANT
IMPACTS NEXT WEEK. ADDITIONAL CHANCES OF PRECIPITATION AND COOL
WEATHER CONTINUING THROUGH FRIDAY.
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
A BAND OF HIGH CLOUDS CONTINUES TO LIFT NORTHEAST ACROSS THE
REGION AHEAD OF A LARGE UPPER LEVEL TROUGH. THE MAIN TROUGH AXIS
WILL MOVE ACROSS CALIFORNIA LATE THIS MORNING INTO THE AFTERNOON.
FORCING WILL BE WEAK AS THE VORT MAX PASSES WELL TO OUR SOUTH, AND
MOISTURE IS GENERALLY CONFINED TO THE 700-400 MB LAYER, SO ANY
PRECIPITATION GENERATED BY THIS SYSTEM WILL BE LIGHT. THERE IS A
15% CHANCE OF SHOWERS OVER THE MOUNTAINS TODAY, BUT WITH A VERY
DRY SUBCLOUD LAYER LOWER ELEVATION LOCATIONS SHOULD REMAIN DRY.
VERY WEAK OFFSHORE FLOW DEVELOPING LATER THIS MORNING WILL
CONTRIBUTE TO MINOR WARMING TODAY WITH HIGHS A COUPLE DEGREES
ABOVE NORMAL. WARM AND DRY ON SATURDAY UNDER WEAK TRANSITORY
RIDGING.
AN UPPER LEVEL LOW CURRENTLY OVER THE GULF OF ALASKA WILL DROP
SOUTH THIS WEEKEND, CLOSING OFF JUST OFF THE NORTHERN CA COAST ON
SUNDAY WITH TROUGHING BEGINNING TO OVERSPREAD SOUTHERN CA. THIS
WILL BRING COOLER WEATHER ALONG WITH AN INCREASE IN SOUTH TO
SOUTHWEST WINDS OVER THE MOUNTAINS AND DESERTS, MOST NOTABLY IN
SAN BERNARDINO COUNTY.
00Z ENSEMBLES ARE COMING INTO BETTER AGREEMENT WITH THE TIMING OF
THE INITIAL SHORT WAVE AND ASSOCIATED ATMOSPHERIC RIVER, WHICH
WILL BRING WIDESPREAD MODERATE TO HEAVY RAIN, MOUNTAIN SNOW, AND
GUSTY WINDS TO THE REGION. THERE IS A SLIGHT (10-15%) CHANCE OF
THUNDERSTORMS MONDAY EVENING AS COLDER AIR ALOFT BEGINS TO MOVE
IN. BASED ON CURRENT TIMING, THE AR AND HEAVIEST PRECIPITATION
WOULD OCCUR DURING THE DAY MONDAY. THE EPS AND GEFS CONTROL RUNS
ARE ON THE STRONGER END OF THE ENSEMBLE GUIDANCE, SHOWING PEAK
INTEGRATED VAPOR TRANSPORT (IVT) OF JUST OVER 500 KG/M/S, THOUGH
THE PROBABILITY OF IVT OF 500 KG/M/S FROM EACH OF THE ENSEMBLE
SYSTEMS IS ONLY IN THE 25-30% RANGE.
SNOW LEVELS AT THE ONSET OF PRECIPITATION SUNDAY NIGHT WILL BE IN
THE 5500-6000 FT RANGE, RISING TO 7000-7500 FT MONDAY MORNING
WITH THE ARRIVAL OF THE AR, THEN FALLING TO 6000-6500 FT MONDAY
EVENING, AND AS LOW AS 5000-5500 FT TUESDAY MORNING.
ADDITIONAL WEAK SHORT WAVES WILL MOVE THROUGH THE MEAN TROUGH ON
TUESDAY, MAINTAINING COOL AND UNSETTLED WEATHER WITH PERIODS OF
LIGHT TO MODERATE SHOWERS CONTINUING. SNOW LEVELS WILL REMAIN NEAR
5000-5500 FT DURING THE DAY TUESDAY. THE MAIN TROUGH AXIS BEGINS
TO PUSH EAST ON WEDNESDAY WITH SNOW LEVELS FALLING TO AROUND
4000-5000 FT BY WEDNESDAY MORNING. THERE ARE STILL SOME TIMING
UNCERTAINTIES ON HOW QUICKLY THIS TROUGH WILL EJECT LATE WEDNESDAY
OR EARLY THURSDAY. IT IS FOLLOWED BY ANOTHER REINFORCING SHORT
WAVE DROPPING SOUTH ALONG THE WEST COAST THURSDAY AND FRIDAY,
MAINTAINING CHANCES OF PRECIPITATION (20-40% THURSDAY LOWERING TO
15-25% FRIDAY). SNOW LEVELS COULD DROP AS LOW AS 3500 FT THURSDAY
MORNING ACROSS THE SAN BERNARDINO MOUNTAINS. WHILE PRECIPITATION
IS CURRENTLY FORECAST TO BE LIGHT DURING THIS PERIOD, ACCUMULATING
SNOW NEAR CAJON SUMMIT (I-15) CAN'T BE RULED OUT, WHICH WOULD MAKE
FOR HAZARDOUS TRAVEL CONDITIONS.
IN TERMS OF PRECIPITATION AMOUNTS, FOR THE 48 HR PERIOD FROM 4 AM
MONDAY - 4 AM WEDNESDAY, THE NBM CHANCES FOR AT LEAST 0.50" ARE
AROUND 80-100% FOR THE MOUNTAINS WESTWARD, 40-70% OVER THE HIGH
DESERT, AND 15-35% OVER THE LOW DESERTS, LOCALLY UP TO 50% NEAR
THE SAN GORGONIO PASS. CHANCES OF AT LEAST 1" ARE ARE AROUND
40-75% FOR THE COASTS AND VALLEYS, 75-100% FOR THE MOUNTAINS,
10-15% FOR THE HIGH DESERT, AND LESS THAN 10% FOR THE LOW DESERT.
AT THE 6500 FT LEVEL IN THE SAN BERNARDINO AND RIVERSIDE COUNTY
MOUNTAINS, THERE IS AROUND A 75% CHANCE OF AT LEAST 12" OF SNOW
DURING THIS SAME 48 HR PERIOD, AND AROUND A 35% CHANCE DOWN AT THE
5000 FT LEVEL. GIVEN THE HIGHER SNOW LEVELS IN SAN DIEGO COUNTY,
CHANCES OF AT LEAST 12" AT PALOMAR AND MOUNT LAGUNA ARE AROUND
20%.
FOR THE 48 HR PERIOD FROM 4 AM WEDNESDAY - 4 AM FRIDAY, NBM MEAN
PRECIPITATION ACCUMULATIONS ARE CLOSER TO 0.20-0.40" FOR THE
COASTS AND VALLEYS, 0.30-0.70" IN THE MOUNTAINS WITH ISOLATED
AMOUNTS NEAR 1" IN THE EASTERN SAN GABRIEL MOUNTAINS, 0.10-0.20"
IN THE HIGH DESERT, AND LESS THAN 0.10" IN THE LOW DESERTS.
ANOTHER 4-8" OF SNOW (NBM MEAN) COULD FALL IN THE MOUNTAINS ABOVE
5000 FT.
AS FAR AS STORM TOTAL RAINFALL/LIQUID-EQUIVALENT, THE OFFICIAL
FORECAST CURRENTLY HAS AROUND 2-3" FOR THE COASTS AND VALLEYS,
2-5" IN THE MOUNTAINS WITH LOCAL AMOUNTS TO 7", 1-1.5" IN THE HIGH
DESERT, AND 0.40-1" IN THE LOW DESERTS WITH LOCAL AMOUNTS NEAR 2"
NEAR THE SAN GORGONIO PASS, WHICH COULD BRING INCREASED FLOWS
IN THE WHITEWATER RIVER.
AVIATION
131030Z...HIGH CLOUDS WILL CONTINUE MOVING EAST OUT OF THE AREA BY
16Z. PATCHY LOW CLOUDS HAVE A 30% CHANCE OF IMPACTING KSAN BETWEEN
12-16Z. ANY LOW CLOUDS WILL BE BASED BETWEEN 1000-2000 FEET MSL.
MOSTLY CLEAR CONDITIONS WILL PREVAIL THEREAFTER, EXCEPT FOR BKN
CUMULUS CLOUDS AROUND 9000 FEET MSL OVER MOUNTAINS AND A 15% CHANCE
OF -SHRA NEAR THE MEXICO BORDER 17-00Z.
MARINE
NO HAZARDOUS MARINE CONDITIONS ARE EXPECTED THROUGH SUNDAY NIGHT. A
STORM SYSTEM WILL GENERATE HAZARDOUS WINDS AND WAVES MONDAY THROUGH
AT LEAST TUESDAY. THERE IS ALSO A SLIGHT CHANCE OF THUNDERSTORMS
NEAR SHORE MONDAY EVENING.
SKYWARN
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
SGX WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...NONE.
PUBLIC...SS
AVIATION/MARINE...MM
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