335
FXUS02 KWNH 290712
PREEPD
EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
311 AM EDT SUN JUN 29 2025
VALID 12Z WED JUL 02 2025 - 12Z SUN JUL 06 2025
..A PROTRACTED WET PERIOD FOR PARTS OF NORTH-CENTRAL FLORIDA
...SOUTHWEST TO SOUTHERN ROCKIES/HIGH PLAINS MONSOONAL FLOW AS THE
TROPICS ACTIVATE OVER THE EASTERN PACIFIC AND BAY OF CAMPECHE...
..GUIDANCE/PREDICTABILITY ASSESSMENT
LATEST MODEL GUIDANCE OFFERS AVERAGE TO BETTER FLOW PREDICTABILITY
OVERALL, BUT DOES SHOW A BIT MORE FORECAST SPREAD THAN HAS BEEN
THE CASE OVER THE PAST FEW DAYS. THIS IS DESPITE BEING REASONABLY
WELL CLUSTERED WITH LARGER SCALE FEATURE EVOLUTIONS OVER THE NEXT
WEEK. THE MOST PRONOUNCED DIFFERENCES REMAIN WITH THE HANDLING OF
NORTHERN AND SOUTHERN STREAM PACIFIC UPPER TROUGH ENERGIES MOVING
INLAND AND OVER THE WEST, AS WELL AS WITH NORTHERN STREAM SYSTEM
PROGRESSION AND AMPLITUDE WORKING DOWNSTREAM FROM SOUTHERN CANADA
THROUGH THE NORTH-CENTRAL TO NORTHEAST/EASTERN U.S STATES. GUIDANCE
DOES PROVIDE SIGNAL FOR MONSOON FLOW EMERGENCE INTO THE SOUTHWEST
WITH SOME CONNECTION TO TROPICAL ACTIVITY OVER THE EASTERN PACIFIC
OFFSHORE MEXICO (EP95) AND FROM THE BAY OF CAMPECHE WITH T.D. TWO.
A FAVORED COMPOSITE BLEND FEATURING COMPATIBLE 18 UTC GEFS MEAN
AND THE 12 UTC ECMWF/CANADIAN ENSEMBLE MEAN SHOULD TEND TO ADDRESS
THESE SMALL-MID SCALE DIFFERENCES CONSISTENT WITH INDIVIDUAL
SYSTEM PREDICTABILITY. THIS STRATEGY MAINTAINS GOOD WPC PRODUCT
CONTINUITY AS OVERALL IN LINE WITH THE 01 UTC NATIONAL BLEND OF
MODELS, MOST MACHINE LEARNING TOOLS AND LATEST 00 UTC GUIDANCE.
..WEATHER/HAZARDS HIGHLIGHTS
THUNDERSTORMS WITH DEEP MOISTURE/INSTABILITY WILL BRING HEAVY
CONVECTIVE DOWNPOURS AHEAD OF A UPPER TROUGH AND SURFACE FRONT
INTO MID-LATE WEEK WHERE WPC EXCESSIVE RAINFALL OUTLOOK (ERO)
MARGINAL RISK AREAS EXIST DAY 4/WEDNESDAY AND DAY 5/THURSDAY. A
FOCUS FOR MULTI-DAY HEAVY RAINS SHOULD SLOWLY SHIFT TO GULF
COASTAL NORTH-CENTRAL FLORIDA WHERE A SLIGHT RISK AREA HAS BEEN
INTRODUCED INTO DAY 5/THURSDAY GIVEN PRECURSOR AND ONGOING HEAVY
RAINFALL POTENTIAL SEEMINGLY REASONABLE IN GUIDANCE GIVEN RIGHT
ENTRANCE REGION UPPER JET SUPPORT AND ANOMOLOUS GULF MOISTURE.
ACTIVITY MAY SHIFT SOUTHWARD OVER FLORIDA INTO NEXT WEEKEND.
MONSOONAL MOISTURE WITH SOME CONNECTION TO EMERGING EASTERN
PACIFIC (EP95) AND BAY OF CAMPECHE (T.D. TWO) TROPICAL FEATURES IS
LIKELY TO INCREASE COVERAGE AND POTENTIAL OF RAIN AMOUNTS INTO MID-
LATER THIS WEEK INTO THE SOUTHWEST AND SOUTHERN ROCKIES/HIGH PLAINS
ON THE WESTERN PERIPHERY OF A WARMING CENTRAL U.S. UPPER RIDGE.
ERO MARGINAL RISK AREAS ARE PLANNED THERE FOR DAY 4/WEDNESDAY AND
DAY 5/THURSDAY SO FAR. AREAS LIKE THE SACRAMENTO MOUNTAINS, WHERE
THE STEEP TERRAIN AND BURN SCARS CAUSE THE AREA TO BE PARTICULARLY
SENSITIVE TO RAIN AND MOST VULNERABLE TO POTENTIAL FLASH FLOODING,
ESPECIALLY WITH WET ANTECEDENT CONDITIONS THERE.
ELSEWHERE, PERIODIC AFTERNOON AND NOCTURNAL STRONG TO SEVERE
STORMS
OFFER A VARIED GUIDANCE SIGNAL TO MONITOR FOR HEAVY RAIN/RUNOFF
POTENTIAL TO EMERGE MORE CLEARLY OUT FROM THE NORTHERN ROCKIES TO
FOCUS LOCALLY OVER THE NORTHERN PLAINS AND UPPER MIDWEST MIDWEEK
INTO NEXT WEEKEND AS UPPER TROUGH/IMPULSE ENERGIES WORK ON
MOISTURE/INSTABILITY POOLING NEAR WAVY PASSING AND DRAPING FRONTS.
SCHICHTEL
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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