Area Forecast Discussion
Issued by NWS Tucson, AZ

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS65 KTWC 310935
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
235 AM MST SAT JAN 31 2015

.SYNOPSIS...A STORM SYSTEM WILL CONTINUE TO BRING VALLEY RAIN AND
MOUNTAIN SNOW TODAY...WITH ACTIVITY DIMINISHING FROM NORTHWEST TO
SOUTHEAST THIS EVENING THROUGH SUNDAY. MINOR FLOODING WILL OCCUR
DUE TO PERIODS OF HEAVY RAINFALL. THE MOST SIGNIFICANT SNOWFALL
WILL BE ACROSS THE HIGHEST PEAKS...ABOVE 8000 FEET. EXPECT MUCH
COOLER DAYTIME TEMPERATURES THIS WEEKEND. DRY CONDITIONS WITH A
WARMING TREND WILL THEN OCCUR DURING THE UPCOMING WEEK.

&&

.DISCUSSION...AN UPPER LOW REMAINS QUASI-STATIONARY OVER SOUTHERN
CALIFORNIA/WESTERN ARIZONA. THERE IS ANOTHER LOW ROUNDING THE MAIN
LOW THIS MORNING. AHEAD OF THE SECONDARY LOW THERE HAS BEEN AN IMPULSE
MOVING ACROSS NORTHERN SONORA MEXICO THIS MORNING. THERE HAS BEEN
SOME LIGHTNING STRIKES ASSOCIATED WITH THIS IMPULSE...THOUGH THEY
HAVE REMAINED SOUTH OF THE BORDER. THE AFOREMENTIONED SECONDARY
LOW ROUNDING THE MAIN LOW HOWEVER WILL LIKELY KICK THE LIGHTNING
ACTIVITY NORTH OVER THE NEXT COUPLE OF HOURS. THEREFORE...HAVE
HIGHLIGHTED ISOLATED THUNDER IN THE WEATHER GRIDS THIS MORNING.
ISOLATED MENTION SPREADS TO AREAWIDE BY THE AFTERNOON AS GUIDANCE
CONTINUES TO SHOW SOME MARGINAL CAPE ACROSS THE FORECAST AREA.

ALSO...BY THIS AFTERNOON THE CALIFORNIA CENTERED LOW WILL FINALLY
EJECT SOUTHWARD AND PHASE INTO THE SOUTHERN LOW THAT IS CURRENTLY
ROUNDING IT. THIS WILL LIKELY BE THE BEGIN OF THE END FOR
SHOWERS...ESPECIALLY ACROSS THE NORTHWEST. THAT BEING SAID...THERE
IS ENOUGH MOISTURE LINGERING AROUND FOR SOME CONTINUAL SHOWERS
DURING THE EVENING AND OVERNIGHT HOURS. THOUGH THE MAIN ACTIVITY
WILL BE ACROSS THE SOUTH TIER OF ZONES. NEVERTHELESS...SHOULD HAVE
THE FORECAST AREA SHOWER FREE BY SUNDAY LATE AFTERNOON.

FROM SUNDAY EVENING ON THE FORECAST REMAINS DRY AS UPPER LEVEL
RIDGE SLIDES OVERHEAD. THIS WILL ALLOW FOR TEMPERATURE TO BOUNCE
BACK TO NEAR WHAT THE AREA WAS SEEING PRIOR TO THE SHOWERS.

CONTINUED FLOOD THREAT TODAY...THE WIDESPREAD SHOWERS HAVE
CONTINUED AND ARE EXPECTED TO CONTINUE THROUGHOUT THE DAY TODAY.
GIVEN THE ALREADY SATURATED SOILS AND STREETS ANY ADDITIONAL
SHOWERS WILL LIKELY RUNOFF AND POND ON ROADWAYS OR ADD TO RISING
WASHES AND RIVERS. CONFIDENCE IN AREAS OF FLOODING TODAY IS HIGH.
CONFIDENCE IN LOCATION OF THIS FLOODING REMAINS LOW.

SNOW LEVELS WILL CONTINUE TO SLOWLY LOWER TODAY WHICH WILL ALLOW
SOME LOCATIONS BETWEEN 7500-8500 FT TO PICK UP SOME. ABOVE THIS
LEVEL AN ADDITIONAL 6 INCHES WILL BE POSSIBLE...WITH THE CENTRAL
SKY ISLANDS POTENTIALLY RECEIVING A LITTLE MORE THAN THAT. SO WILL
KEEP WINTER STORM WARNING IN PLACE AS IS.

&&

.AVIATION...VALID THRU 01/12Z.
SCATTERED TO WIDESPREAD VALLEY RAIN AND MOUNTAIN SNOW WILL CONTINUE
TODAY. AREAS OF PATCHY FOG THIS MORNING WILL CAUSE WIDESPREAD MVFR
CONDITIONS AND LOCAL IFR CONDITIONS. THERE IS A SLIGHT CHANCE OF
-TSRA ACROSS MUCH OF THE AREA THROUGH THIS EVENING. CLOUD DECKS OF
2-3K FT AGL ARE LIKELY IN SHOWERS AND THUNDERSTORMS. OUTSIDE OF
PRECIPITATION...EXPECT BKN-OVC CLOUDS AT 4-8K FT AGL. SLY/SWLY WINDS
AT 5-15 KTS TODAY WILL WEAKEN THIS EVENING TO LESS THAN 10 KTS.
PRECIPITATION WILL BEGIN TO END FROM WEST TO EAST SUNDAY WITH
SCATTERED SHOWERS LIKELY MAINLY SOUTH AND EAST OF TUCSON. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...EXPECT SCATTERED TO WIDESPREAD VALLEY RAIN AND
MOUNTAIN SNOW TODAY ALONG WITH WITH A FEW RUMBLES OF THUNDER AS A
LOW PRESSURE SYSTEM MOVES ACROSS THE AREA. A FEW LINGERING SHOWERS
WILL OCCUR MAINLY EAST TO SOUTH OF TUCSON SUNDAY. DRY CONDITIONS
WILL RETURN SUNDAY NIGHT AND LAST THROUGH THE UPCOMING WORK WEEK.
20-FT WINDS TODAY WILL GENERALLY BE SLY AT 5-15 MPH. ELEVATED WEST
TO NORTHWEST WINDS MAY OCCUR WEDNESDAY AFTERNOON IN LOCATIONS
ADJACENT THE NEW MEXICO BORDER AND THE GILA RIVER VALLEY. EASTERLY
WINDS ARE EXPECTED THURSDAY NIGHT INTO FRIDAY WITH A FEW HIGHER
GUSTS POSSIBLE. OTHERWISE...WINDS WILL GENERALLY BE LESS THAN 10
MPH.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL NOON MST TODAY FOR AZZ510>512-514.

&&

$$

DISCUSSION...MEADOWS
FIRE WEATHER/AVIATION...81

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON







USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.