440
FXUS02 KWBC 251756
PMDEPD
EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1256 PM EST WED FEB 25 2026
VALID 12Z SAT FEB 28 2026 - 12Z WED MAR 04 2026
..OVERVIEW
BROAD TROUGHING WILL BE PRESENT ACROSS THE EASTERN HALF OF THE
COUNTRY WHILE RIDGING EXISTS ACROSS THE SOUTHWEST TO START THE
MEDIUM RANGE PERIOD SATURDAY. OVER THE WEEKEND, A STRONG COLD
FRONT AND ARCTIC HIGH PRESSURE WILL MOVE INTO THE NORTHERN TIER,
BRINGING COLDER TEMPERATURES. UNDER THE SOUTHWEST RIDGE, ABOVE
NORMAL TEMPERATURES ARE EXPECTED, WITH HIGHS IN THE 90S POTENTIALLY
BREAKING RECORDS IN THE DESERT SOUTHWEST. AS THE HIGH PRESSURE
RETREATS OFF TO THE NORTHEAST, PACIFIC SHORTWAVE ENERGY AND
MOISTURE MAY OVERRUN THIS COLDER AIRMASS SUNDAY INTO TUESDAY
BRINING A WINTRY PRECIPITATION THREAT TO PORTIONS OF THE MS VALLEY
INTO THE MID-ATLANTIC AND NORTHEAST.
..GUIDANCE/PREDICTABILITY ASSESSMENT
OVERALL GOOD AGREEMENT ACROSS THE MODELS WITH TROUGHING OVER THE
EAST AND RIDGING OVER THE WEST. AN ARCTIC HIGH AND COLD FRONT WILL
DROP SOUTH ACROSS THE PLAINS AND EAST COAST THIS WEEKEND INTO
EARLY NEXT WEEK. WHILE THIS SYNOPTIC EVOLUTION FEATURES AVERAGE TO
BELOW AVERAGE MODEL SPREAD, THE EXACT STRENGTH AND TIMING OF THESE
FEATURES WILL SIGNIFICANTLY IMPACT THE TEMPERATURE FORECAST ACROSS
THE COUNTRY. A MULTI MODEL BLEND SHOULD SUFFICE TO CAPTURE A MIDDLE
GROUND OUTCOME, BUT THERE IS AN UNUSUALLY LARGE SPREAD BETWEEN THE
25TH AND 75TH PERCENTILES OF THE NBM...HIGHLIGHTING THE
TEMPERATURE UNCERTAINTY NEAR THE BAROCLINIC ZONE, BOTH ACROSS THE
MIDDLE OF THE COUNTRY AND WITHIN THE EXPECTED COLD AIR DAMMING
REGIME OVER THE MID-ATLANTIC.
TOWARD THE LATTER PORTION OF THE PERIOD, THE MODELS SPREAD INCREASES
AS THE CLOSED LOW OVER THE PACIFIC PUSHES INTO CA, WHILE A ZONAL
FLOW FORMS ACROSS MUCH OF CONUS CREATING NORTH-SOUTH TEMPERATURE
GRADIENT. DETERMINISTIC MODELS SHOW RUN-TO-RUN DIFFERENCES FOR THE
TIMING, INTENSITY, AND PROGRESSION OF THE EMBEDDED ENERGY TOWARDS
PORTIONS OF EASTERN U.S. MODEL DIFFERENCES SEEM TO RELATE TO BOTH
HOW QUICKLY THE NORTHEAST TROUGH EXITS, AND HOW MUCH SHORTWAVE
ENERGY GETS EJECTED EASTWARD ACROSS THE COUNTRY, BOTH FROM THE
CLOSED LOW AND THE NORTHERN STREAM. WITH THE RETREATING ARCTIC HIGH
THE PATTERN WOULD FAVOR A WINTRY PRECIPITATION RISK FROM PORTIONS OF
THE MS VALLEY INTO THE MID- ATLANTIC AND NORTHEAST IF ANY
APPRECIABLE PACIFIC ENERGY IS ABLE TO EJECT EASTWARD. THERE
CONTINUES TO BE RATHER LARGE RUN TO RUN VARIABILITY WITH THESE
DETAILS, ALTHOUGH SOME ASPECTS OF THE FORECAST APPEAR A BIT MORE
CLEAR THAN THEY WERE YESTERDAY. IT LOOKS LIKE ONE WAVE ALONG THE
BAROCLINIC ZONE WILL TRACK EASTWARD SUNDAY INTO MONDAY BRINGING A
WINTRY MIX TO PORTIONS OF THE MS VALLEY INTO THE MID-ATLANTIC AND
NORTHEAST. THERE ARE MAGNITUDE AND LATITUDINAL DIFFERENCES IN THE
MODELS HOWEVER, WITH THE GFS ON THE STRONG/NORTH SIDE OF THE MODEL
SPREAD AND THE AIFS THE FARTHEST SOUTH.
ADDITIONAL UPSTREAM ENERGY, FROM BOTH THE NORTHERN STREAM AND
ENERGY EJECTING OUT OF THE CLOSED LOW OVER THE SOUTHWEST, SHOULD
RESULT IN ANOTHER ROUND, OR CONTINUATION, OF PRECIPITATION
OVERRUNNING THE HIGH PRESSURE INTO TUESDAY.
..WEATHER/HAZARDS HIGHLIGHTS
THE BIGGEST PRECIPITATION RELATED IMPACTS THIS PERIOD WILL RESULT
FROM THE POTENTIAL OF OVERRUNNING WINTER PRECIPITATION FROM THE MS
VALLEY INTO THE NORTHEAST SUNDAY INTO TUESDAY. AS MENTIONED ABOVE,
THE OVERALL PATTERN WOULD FAVOR A WINTRY MIX OF PRECIPITATION
TYPES AS SHORTWAVE ENERGY/MOISTURE OVERRUNS THE RETREATING ARCTIC
HIGH PRESSURE. THE MORE ENERGY THAT EJECTS OUT OF THE WEST COAST
TROUGH/CLOSED LOW AND THE MORE SIGNIFICANT THE PRECIPITATION RISK.
THE FIRST WAVE SHOULD IMPACT THE MS VALLEY AND OH VALLEY SUNDAY,
SPREADING INTO THE MID-ATLANTIC AND NORTHEAST MONDAY. THE GFS IS
MOST AGGRESSIVE WITH THIS FEATURE, WITH THE HIGHEST QPF AND A
FARTHER NORTH AXIS...WITH THE AIFS THE FARTHEST SOUTH (WEAKER WITH
THE SHORTWAVE ENERGY AND STRONGER/SLOWER WITH THE EXITING HIGH
PRESSURE). WHILE NOT EXPECTED TO BE A MAJOR STORM, IT DOES SEEM
PROBABLE THAT A SWATH OF PLOWABLE SNOWFALL WILL ACCOMPANY THIS
SYSTEM, BUT A LOT OF UNCERTAINTY REGARDING THE EXACT AXIS AND
MAGNITUDES. THE SETUP SHOULD ALSO SUPPORT A SWATH OF SLEET AND
FREEZING RAIN, BUT THIS CORRIDOR SHOULD BE PRETTY NARROW, WITH EVEN
MORE UNCERTAINTY WITH THOSE DETAILS.
THE SECOND ROUND OF PRECIPITATION IS EXPECTED TUESDAY. WITH THE
RETREATING HIGH PRESSURE OVER THE NORTHEAST AND RESULTANT COLD AIR
DAMMING, WOULD WOULD EXPECT TO SEE A WINTRY MIX OF PRECIPITATION
FROM THE NORTHERN MID-ATLANTIC INTO THE NORTHEAST. FARTHER WEST,
THE APPROACH OF THE CLOSED LOW INTO THE FOUR CORNERS REGION SHOULD
RESULT IN AN UPTICK IN PRECIPITATION ACROSS THE SOUTHERN PLAINS,
POTENTIALLY SPREADING INTO MS/TN VALLEY AS MOISTURE ADVECTS NORTH
INTO THE LINGERING BAROCLINIC ZONE. THIS CLOSED LOW WILL BE PRETTY
SEPARATED FROM THE NORTHERN STREAM BY THIS TIME...SO IT SHOULD BE A
WARM SYSTEM, WITH MAINLY RAIN. THUS THE MAIN WINTER HAZARDS BY
TUESDAY SHOULD BE CONFINED PRIMARILY TO THE NORTHEAST, CLOSER TO
THE RETREATING HIGH PRESSURE WHERE COLD AIR WILL HANG IN LONGER.
THE SOUTHWEST INTO THE SOUTHERN PLAINS WILL CONTINUE TO BE MUCH
WARMER THAN AVERAGE ON SATURDAY DUE TO THE UPPER RIDGE OVER THE
SOUTHWEST. THE SOUTHWEST INTO THE PLAINS CAN EXPECT TEMPERATURES OF
15 TO 25 DEGREES ABOVE AVERAGE, WHICH RESULTS IN 80S AND 90Z FROM
THE DESERT SOUTHWEST INTO THE SOUTHERN PLAINS. HOWEVER, A STRONG
COLD FRONT CARRYING AN AIRMASS FROM ALASKA AND VICINITY WILL BRING
MUCH COLDER TEMPERATURES TO THE NORTHERN TIER BY THE WEEKEND.
SINGLE DIGIT HIGHS AND LOWS BELOW 0F ARE LIKELY FOR PARTS OF NORTH
DAKOTA/MINNESOTA, WITH WIND CHILLS AS LOW AS 20 TO 30 DEGREES BELOW
ZERO. AHEAD OF THIS FRONT UNSEASONABLY WARM TEMPERATURES CONTINUE
ACROSS PORTIONS OF THE SOUTHERN TIER. IN THE EAST, ABOVE AVERAGE
TEMPERATURES ARE EXPECTED OVER THE WEEKEND, UNTIL THE COLD FRONT
REACHES THE NORTHEAST AND MID-ATLANTIC WITH COLDER TEMPERATURES BY
LATE SUNDAY INTO TUESDAY.
OUDIT/CHENARD
ADDITIONAL 3-7 DAY HAZARD INFORMATION CAN BE FOUND ON THE WPC
MEDIUM RANGE HAZARDS OUTLOOK CHART AT:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP
WPC MEDIUM RANGE 500MB HEIGHTS, SURFACE SYSTEMS, WEATHER GRIDS,
QUANTITATIVE PRECIPITATION FORECAST (QPF), EXCESSIVE RAINFALL
OUTLOOK (ERO), WINTER WEATHER OUTLOOK (WWO) PROBABILITIES, HEAT
INDICES, AND KEY MESSAGES CAN BE ACCESSED FROM:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST500_WBG.GIF
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST_WBG_CONUS.GIF
HTTPS://WWW.WPC.NCEP.NOAA.GOV/5KM_GRIDS/5KM_GRIDSBODY.HTML
HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/DAY4-7.SHTML
HTTPS://WWW.WPC.NCEP.NOAA.GOV/#PAGE=ERO
HTTPS://WWW.WPC.NCEP.NOAA.GOV/WWD/PWPF_D47/PWPF_MEDR.PHP?DAY=4
HTTPS://WWW.WPC.NCEP.NOAA.GOV/HEAT_INDEX.SHTML
HTTPS://WWW.WPC.NCEP.NOAA.GOV/#PAGE=OVW
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