Prognostic Meteorological Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1
000
FXUS21 KWNC 281800
PMDTHR
US HAZARDS OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EDT MAY 28 2015

SYNOPSIS: AT THE START OF THE PERIOD, A FRONTAL SYSTEM IS EXPECTED TO EXTEND
SOUTHWESTWARD FROM NEW ENGLAND ACROSS THE OHIO AND LOWER MISSISSIPPI VALLEYS TO
THE SOUTHERN PLAINS. THE FRONT IS FORECAST TO MOVE SLOWLY SOUTHEASTWARD BEFORE
STALLING AND EVENTUALLY DISSIPATING OVER THE SOUTHEAST U.S. SOUTH OF THE FRONT,
MOIST EASTERLY FLOW IS EXPECTED OVER PARTS OF CENTRAL AND SOUTHERN FLORIDA.
SURFACE  LOW PRESSURE IS EXPECTED OVER THE NORTHERN ROCKIES/NORTHERN PLAINS
JUNE 1. THIS AREA OF LOW PRESSURE AND ITS ASSOCIATED FRONTAL SYSTEMS ARE
FORECAST TO MOVE SLOWLY SOUTH/SOUTHEASTWARD. A COLD FRONT IS FORECAST TO CROSS
THE BROOKS RANGE OF ALASKA MAY 31-JUN 1. AN AREA OF DISTURBED WEATHER SOUTH OF
THE MEXICAN COAST IS FORECAST TO TRACK TOWARDS THE WEST-NORTHWEST.



HAZARDS

HEAVY RAIN FOR PARTS OF THE TENNESSEE VALLEY, CENTRAL AND SOUTHERN
APPALACHIANS, MID-ATLANTIC, AND NORTHEAST, SUN-MON, MAY 31-JUN 1.

HEAVY RAIN FOR PARTS OF CENTRAL AND SOUTHERN FLORIDA, MON-WED, JUN 1-JUN 3.

HEAVY RAIN FOR PARTS OF NORTH-CENTRAL MONTANA, MON, JUN 1.

HEAVY RAIN FOR PARTS OF THE CENTRAL AND NORTHERN PLAINS, TUE-WED, JUN 2-3.

ENHANCED WILDFIRE RISK FOR INTERIOR EASTERN ALASKA NORTH OF THE ALASKA RANGE,
SUN-MON, MAY 31-JUN 1.

ENHANCED WILDFIRE RISK FOR INTERIOR EASTERN ALASKA SOUTH OF THE ALASKA RANGE,
SUN-THU, MAY 31-JUN 4.

FLOODING IS POSSIBLE, IMMINENT, OR OCCURRING ACROSS PORTIONS OF THE CENTRAL AND
WEST-CENTRAL CONUS.

SEVERE DROUGHT FOR PARTS OF THE NORTHERN GREAT PLAINS, SOUTHWEST, GREAT BASIN,
CALIFORNIA, AND THE PACIFIC NORTHWEST.

DETAILED SUMMARY

FOR SUNDAY MAY 31 - THURSDAY JUNE 04: AN UPPER-LEVEL RIDGE IS EXPECTED TO LEAD
TO VERY WARM DAILY MAXIMUM TEMPERATURES (POSITIVE ANOMALIES OF 10-15 DEGREES F)
FOR PARTS OF THE NORTHWESTERN CONUS MAY 31. WHILE SOME LOCATIONS MAY APPROACH
90 DEGREES F, A HAZARD SHAPE IS NOT DEEMED WARRANTED.



AT THE START OF THE PERIOD A FRONTAL SYSTEM IS FORECAST TO STRETCH
SOUTHWESTWARD FROM NEW ENGLAND ACROSS THE OHIO AND LOWER MISSISSIPPI VALLEYS TO
THE SOUTHERN PLAINS. AS THE FRONT MOVES SLOWLY SOUTHEASTWARD IT IS EXPECTED TO
ACT AS A FOCUSING MECHANISM FOR SHOWERS AND THUNDERSTORMS. HEAVY RAIN (IN
EXCESS OF 1 INCH IN 24 HOURS) IS EXPECTED FOR PARTS OF THE TENNESSEE VALLEY,
CENTRAL AND SOUTHERN APPALACHIANS, MID-ATLANTIC, AND NORTHEAST MAY 31-JUN 1.
THUNDERSTORMS ARE LIKLEY DURING THE PERIOD OVER THESE REGIONS BUT MODEL
UNCERTAINTY PRECLUDES THE SPECIFICATION OF A SEVERE WEATHER HAZARD AT THE
CURRENT TIME. SOUTH OF THE FRONT, MOIST EASTERLY FLOW IS EXPECTED TO GET
ESTABLISHED OVER FLORIDA LEADING TO HEAVY RAIN (IN EXCESS OF 1 INCH IN 24
HOURS) FOR PARTS OF CENTRAL AND SOUTHERN FLORIDA JUN 1-3.



LOW PRESSURE MOVING ACROSS THE NORTHERN ROCKIES/NORTHERN PLAINS LEADS TO HEAVY
RAIN (IN EXCESS OF 1 INCH IN 24 HOURS) FOR PARTS OF NORTH-CENTRAL MONTANA JUNE
1, AND PARTS OF THE NORTHERN AND CENTRAL PLAINS JUN 2-3. THUNDERSTORMS ARE
EXPECTED FOR PARTS OF THESE REGIONS BUT MODEL UNCERTAINTY PRECLUDES THE
SPECIFICATION OF A SEVERE WEATHER HAZARD SHAPE AT THE CURRENT TIME.



IN THE EASTERN INTERIOR OF ALASKA, A COLD FRONT IS EXPECTED TO MOVE ACROSS THE
BROOKS RANGE AND BRING COOLER CONDITIONS NORTH OF THE ALASKA RANGE. WINDY, DRY
CONDITIONS LEAD TO CRITICAL WILDFIRE CONDITIONS NORTH OF THE ALASKA RANGE MAY
31-JUN 1, AND SOUTH OF THE ALASKA RANGE MAY 31-JUN 4.



NUMEROUS AREAS OF POSSIBLE, LIKELY, IMMINENT, AND OCCURRING FLOODING ARE
INDICATED OVER THE CENTRAL AND WEST-CENTRAL PORTIONS OF THE CONUS, WITH ALL THE
HEAVY RAIN RECEIVED IN RECENT DAYS AND WEEKS. TO OBTAIN THE VERY LATEST,
DETAILED INFORMATION ON THE STATUS OF STREAMS AND RIVERS ACROSS THE U.S.,
PLEASE CONSULT THE RIVER FORECAST CENTER (RFC) HOMEPAGE AT:
HTTP://WATER.WEATHER.GOV/AHPS/RFC/RFC.PHP.

FOR FRIDAY JUNE 05 - THURSDAY JUNE 11: THE EXPECTED MID-TROPOSPHERIC FLOW
PATTERN FOR WEEK-2 FEATURES BASICALLY ZONAL FLOW ACROSS THE NORTHERN HALF OF
THE CONUS. SIGNIFICANT POSITIVE HEIGHT ANOMALIES AT 500-HPA (RANGING FROM +60
TO +100 METERS) ARE FORECAST ACROSS THE NORTHEAST, AND ARE EXPECTED TO COINCIDE
WITH ABOVE NORMAL SURFACE TEMPERATURES DURING THIS PERIOD FOR THAT REGION.
ABOVE NORMAL HEIGHTS OVER THE NORTHWEST INDICATE THE LIKELIHOOD OF ABOVE NORMAL
TEMPERATURES FOR THAT REGION AS WELL.



THE MOST RECENT U.S. DROUGHT MONITOR, RELEASED MAY 28TH, INDICATES A DECREASE
(FROM 15.16 TO 14.20) IN THE PERCENTAGE OF THE CONUS IN SEVERE TO EXCEPTIONAL
DROUGHT (D2-D4). THIS REPRESENTS THE SMALLEST AREAL COVERAGE OF D2-D4 SINCE
MARCH 2011.

FORECASTER: RANDY SCHECHTER

$$



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