886
FXUS02 KWBC 231931
PMDEPD
EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
331 PM EDT THU APR 23 2026
VALID 12Z SUN APR 26 2026 - 12Z THU APR 30 2026
...A LOW PRESSURE SYSTEM WILL CAUSE HEAVY RAIN AND SEVERE WEATHER
ACROSS THE CENTRAL U.S. SUNDAY AND EAST-CENTRAL U.S. MONDAY...
..OVERVIEW
INTO EARLY NEXT WEEK, AN AMPLIFIED AND PROGRESSIVE SPRING PATTERN
CONTINUES ACROSS THE LOWER 48, AS A SURFACE LOW MOVES THROUGH THE
NORTH-CENTRAL U.S., SUPPORTING HEAVY RAIN AND SEVERE WEATHER IN THE
PLAINS AND MISSISSIPPI VALLEY. THE COLD FRONT SHOULD PRESS ACROSS
THE EAST INTO TUESDAY-WEDNESDAY AND BRING RAIN CHANCES THERE,
THOUGH SHOWERS AND THUNDERSTORMS ARE ALSO FORECAST TO LINGER ACROSS
THE SOUTH-CENTRAL TO SOUTHEASTERN U.S. AS A FRONT STALLS SOUTH OF
A BROAD UPPER TROUGH ANCHORED IN SOUTH-CENTRAL CANADA. MEANWHILE, A
SOUTHERN STREAM UPPER LOW WILL MAKE ITS WAY INTO CALIFORNIA AROUND
MIDWEEK AND BRING CHANCES FOR LOW ELEVATION RAIN AND MOUNTAIN SNOW
ACROSS THE INTERMOUNTAIN WEST/ROCKIES INTO THE PLAINS.
..GUIDANCE/PREDICTABILITY ASSESSMENT
AS THE PERIOD BEGINS SUNDAY, TROUGHING ALOFT WILL MOVE QUICKLY
ACROSS THE INTERMOUNTAIN WEST INTO THE CENTRAL PLAINS ROUNDING THE
BASE OF A PERSISTENT SOUTH-CENTRAL CANADA UPPER LOW, SUPPORTING A
SURFACE LOW PRESSURE SYSTEM. RECENT MODEL GUIDANCE REMAINS
REASONABLY AGREEABLE WITH THIS SYSTEM, AND A MULTI-MODEL BLEND LIKE
THE NBM SEEMS TO REPRESENT THE PATTERN WELL. THIS HOLDS AS THE
SURFACE LOW TRACKS INTO THE UPPER MIDWEST/GREAT LAKES BY TUESDAY.
FARTHER EAST, THERE ARE SOME MODEL DISCREPANCIES WITH A SHORTWAVE
OVER THE NORTHEAST AND A SURFACE LOW IN THE WESTERN ATLANTIC EARLY
NEXT WEEK, WHICH WOULD AFFECT RAIN CHANCES AND POTENTIAL WINDS
ACROSS COASTAL AREAS OF THE NORTHEAST. OF THE 12Z MODELS, THE CMC
SEEMS TO LINGER THE FARTHEST WEST (FOR MORE EFFECTS IN THE
NORTHEAST), BUT DOES HAVE SOME SUPPORT FROM THE AI GUIDANCE.
FARTHER WEST, THERE IS GOOD AGREEMENT FOR RIDGING ACROSS THE
NORTHWEST, BUT A SOUTHERN STREAM LOW/TROUGH SHOWS UNCERTAIN TIMING
COMING INTO CALIFORNIA AND THE SOUTHWEST AROUND MIDWEEK. WITH THE
00/06Z MODEL CYCLE, THE ECMWF TRACKED THIS FEATURE MORE QUICKLY
INTO THE COAST COMPARED TO THE GFS/CMC AND EC-AIFS/AIGFS. HOWEVER,
THE FASTER TRACK HAD SUPPORT FROM MOST ENSEMBLE MEMBERS (INCLUDING
CMCE AND GEFS) AND SOME OF THE OTHER EC-BASED AI MODELS. THE 12Z
MODEL GUIDANCE HAS INDEED TRENDED FASTER THAN EARLIER RUNS OF THE
CMC/GFS, FOR BETTER MODEL CONVERGENCE NOW. AS THE PERIOD
PROGRESSED, THE WPC FORECAST USED JUST OVER HALF ENSEMBLE MEANS FOR
DAYS 6-7 DUE TO MODEL DIFFERENCES WITH THE WESTERN LOW.
..WEATHER/HAZARDS HIGHLIGHTS
UPPER TROUGHING MOVING ACROSS THE INTERMOUNTAIN WEST WILL SUPPORT
LOWER ELEVATION RAIN AND TERRAIN ENHANCED SNOW ACROSS THE GREAT
BASIN/ROCKIES AND NORTHERN HIGH PLAINS SUNDAY AND MONDAY, WITH A
LITTLE LINGERING INTO TUESDAY AS ANOTHER FRONT COMES THROUGH. THIS
ENERGY WILL ALSO SET UP A POTENT SURFACE LOW PRESSURE IN THE
CENTRAL U.S. THAT SHOULD SERVE AS A FOCUS FOR HEAVY RAIN AND
THUNDERSTORMS, INCLUDING ORGANIZED CONVECTION. ABOVE AVERAGE
MOISTURE AND INSTABILITY ARE FORECAST TO ADVECT WELL NORTH FROM THE
GULF ACROSS THE PLAINS AND MISSISSIPPI VALLEY, WHILE A COUPLED JET
STRUCTURE PROVIDES UPPER LEVEL SUPPORT. SEVERE WEATHER COULD BE A
SIGNIFICANT THREAT PER THE STORM PREDICTION CENTER. ADDITIONALLY,
MARGINAL RISKS OF FLASH FLOODING ARE IN PLACE FOR THE CENTRAL U.S.
FOR DAY 4/SUNDAY AND SLIGHTLY EAST INTO THE MISSISSIPPI/OHIO VALLEY
AND MID-SOUTH BY DAY 5/MONDAY. THESE WERE EXPANDED SOMEWHAT FROM
THE PREVIOUS ISSUANCES BECAUSE OF THE WIDESPREAD INSTABILITY AND
MOISTURE POTENTIALLY CAUSING ISOLATED FLOODING FROM HIGH RAIN RATES
DESPITE DRY CONDITIONS IN MANY AREAS. MEANWHILE, HIGH WINDS AND
CONDITIONS FAVORABLE FOR FIRE WEATHER ARE LIKELY IN THE
SOUTHWEST/HIGH PLAINS EARLY NEXT WEEK ON THE BACKSIDE OF THE
SYSTEM.
THE COLD FRONT ASSOCIATED WITH THE SURFACE LOW SHOULD TRACK ACROSS
THE EASTERN SEABOARD TUESDAY INTO WEDNESDAY AND SPREAD RAIN AND
THUNDERSTORMS THERE. ADDITIONALLY, CONVECTION IS FORECAST TO LINGER
IN THE SOUTH-CENTRAL TO SOUTHEASTERN U.S. INTO TUESDAY AS A
FRONTAL SYSTEM MEANDERS. THEN THE UPSTREAM SOUTHERN STREAM LOW WILL
SPREAD SOME LIGHT TO MODERATE PRECIPITATION TO CALIFORNIA, THE
SOUTHWEST, AND FOUR CORNERS STATES BY WEDNESDAY, INCLUDING SNOW IN
HIGHER ELEVATIONS OF THE CENTRAL ROCKIES. THIS FEATURE WILL PROVIDE
MORE SUPPORT FOR RENEWED PRECIPITATION IN THE SOUTH-CENTRAL PLAINS
TO LOWER/MIDDLE MISSISSIPPI VALLEY AND MID-SOUTH ON WEDNESDAY INTO
THURSDAY.
WARMER THAN AVERAGE TEMPERATURES ARE LIKELY TO THE SOUTH OF THE
PRIMARY STORM TRACK ACROSS THE SOUTHERN PLAINS THROUGH MIDWEEK, AND
AHEAD OF THE COLD FRONT INTO THE MISSISSIPPI AND OHIO VALLEYS
EARLY NEXT WEEK. TEMPERATURES IN THE 90S WILL BE COMMON ACROSS
TEXAS. MEANWHILE, BELOW AVERAGE TEMPERATURES CONTINUE FOR MUCH OF
THE WEST AND NORTHERN/CENTRAL PLAINS UNDER THE TROUGHING THROUGH
MONDAY, AND SHIFTING INTO THE NORTH-CENTRAL U.S. THROUGH MIDWEEK.
MOST AREAS COULD MODERATE TO NEAR OR BELOW AVERAGE CONDITIONS BY
MID TO LATE NEXT WEEK.
TATE
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, EXCESSIVE RAINFALL OUTLOOK, WINTER WEATHER OUTLOOK PROBABILITIES, HEAT INDICES AND KEY MESSAGES ARE AT:
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
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page