Skip Navigation Linksweather.gov 
NOAA logo - Click to go to the NOAA homepage National Weather Service Forecast Office   NWS emblem - Click to go to the NWS homepage
Sterling, VA banner image
navigation bar image  
  navigation bar image

[facebook] [twitter]

You are at: NWS >> ERH >> LWX >> Product Browser

Area Forecast Discussion

Latest versions:
[Current] [-1] [-2] [-3] [-4] [5] [-6] [-7] [-8] [-9]    [Glossary On]
 
FXUS61 KLWX 151918
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
318 PM EDT TUE APR 15 2014

.SYNOPSIS...

AN EXCEPTIONALLY COLD AIRMASS FOR THIS TIME OF YEAR WILL QUICKLY 
TAKE HOLD OF THE AREA BY LATE THIS EVENING. HIGH PRESSURE WILL BUILD 
OVERHEAD DURING THE MIDDLE OF THE WEEK...THEN MOVE OFFSHORE LATE IN 
THE WEEK. AN AREA OF LOW PRESSURE MAY AFFECT THE AREA DURING THE 
FIRST HALF OF THE WEEKEND.

&&

.NEAR TERM /THROUGH WEDNESDAY/...

COLD FRONT HAS MADE IT THROUGH DCA AND BWI AS OF 2PM..AND PRESSING
QUICKLY SE. TEMPS DROP QUICKLY FROM THE 60S AND LOW 70S INTO THE
50S...WITH 40S SOON TO FOLLOW. DROPPED FROM 68 TO 53 HERE AT
STERLING VA IN 90 MINS. GOOD THING THE COLD FRONT DID WAS UNDERCUT
THE LINE OF CONVECTION THAT WAS DUMPING HEAVY RAIN FOR A TIME OVER
THE METRO AREAS. END OF THE PRECIP IS NOT EXPECTED UNTIL LATER
TONIGHT AND WITH THE COLD AIR CONTINUING TO COME IN...THERE WILL
BE SOME SNOW IN AREAS...MAINLY ABOVE 1500 FEET...BUT COULD EVEN BE
SOME WET NON ACCUM SNOWFLAKES IN THE METRO AREAS AFTER DARK BEFORE
THE PRECIP ENDS. FREEZE WARNING FOR LATE TONIGHT INTO WED MORNING
FOR VEGETATION...BUT ALSO COULD BE SOME ICY SPOTS WED MORN IN
AREAS THAT DONT DRY IN THE OVERNIGHT WIND. HIGHS ONLY AROUND 50 ON
WED UNDER SUNNY SKIES.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...

HIGH PRESSURE WEDNESDAY NIGHT ALONG WITH CLEAR SKIES/LIGHT WINDS
WILL PRODUCE A MORE TYPICAL RADIATIONAL COOLING NIGHT AND
THEREFORE TEMPERATURES ARE EXPECTED TO BOTTOM OUT AGAIN. FREEZE
WATCH HAS BEEN ISSUED EAST OF THE BLUE RIDGE INTO THURSDAY
MORNING.

HIGH PRESSURE CENTER MOVES OFF THE NORTHEAST COAST AND THEN WEDGES 
DOWN THROUGH THE MID-ATLANTIC TO END THE WEEK. TEMPS MAY REBOUND 
SOME...BUT WILL STILL BE BELOW AVERAGE THROUGH FRIDAY. CLOUDS LIKELY 
INCREASE THURSDAY NIGHT INTO FRIDAY WITH A WEAK DISTURBANCE OFF THE 
COAST AND ALSO AHEAD OF THE NEXT UPSTREAM SHORTWAVE TROUGH BUT FAVOR 
A DRY FORECAST ATTM.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

A COUPLE AREAS OF LOW PRESSURE WILL BRUSH PAST THE REGION FOR THE 
FIRST PART OF THIS WEEKEND...WITH A CHANCE OF RAIN MAINLY DURING THE 
DAY SATURDAY. THE MODELS HAVE MOST RECENTLY TRENDED DOWNWARD WITH 
THE PROBABILITY OF RAIN AND WITH RAINFALL AMOUNTS AS A RESULT OF 
ENERGY FROM THE NORTHERN AND SOUTHERN BRANCHES OF THE JET STREAM 
REMAINING SPLIT INSTEAD OF PHASING. THIS LEAVES TO TWO WEAKER WAVES 
OF LOW PRESSURE...ONE PASSING TO THE NORTHWEST ACROSS THE GREAT 
LAKES AND THE OTHER MOVING OFFSHORE INTO THE ATLANTIC.

ANOTHER PUSH OF COOL AIR WILL ACCOMPANY HIGH PRESSURE MOVING DOWN 
FROM CENTRAL CANADA FOR THE SECOND HALF OF THE WEEKEND...THOUGH NOT 
NEARLY AS COLD OF AN AIRMASS AS IS EXPECTED DURING THE MIDDLE OF 
THIS WEEK.

LOW PRESSURE WILL APPROACH THE AREA FROM THE WEST EARLY NEXT WEEK 
BRINGING A CHANCE OF RAIN MONDAY INTO TUESDAY.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...

IFR CONDITIONS UNDER SHOWERS THIS AFTERNOON INTO EVENING. THEN CLEARING.
WINDS ALREADY NW AND GUSTING 18 TO 32KT AT TAF SITES... EXCEPT MTN
WHICH IS IMMINENT.

HIGH PRESSURE WED MOVES OFF THE COAST TOWARD THE END OF THE WEEK. 
ONSHORE FLOW MAY LEAD TO FLIGHT RESTRICTIONS IN LOW CLOUDS THURSDAY 
NIGHT INTO FRIDAY. 

SUB-VFR POSSIBLE IN RAIN SATURDAY...THEN VFR SUNDAY. EASTERLY
WINDS 5 TO 10 KNOTS SATURDAY BECOME WEST OR NORTHWEST AROUND 10
KNOTS BY SUNDAY.

&&

.MARINE...

GALES UP ON THE WATERS...FIRST FOR GUSTY SHOWERS...THEN FOR THE NW
BLAST AFTER THE FRONT WHICH BEGINS MOVING OVER THE WATERS DURING
THE MID AFTERNOON. GALE WARNING IN EFFECT THROUGH THE NIGHT.

SCA CONTINUES INTO MUCH OF WEDNESDAY...BEFORE GRADIENT RELAXES LATER 
IN THE AFTERNOON FOR DIMINISHING WINDS. NO SCA CONDITIONS ARE 
EXPECTED WEDNESDAY NIGHT. MARGINAL SCA POSSIBLY AGAIN LATE THURSDAY 
OR THURSDAY NIGHT WITH EAST WINDS. 

SMALL CRAFT ADVISORY LEVEL WIND GUSTS ARE POSSIBLE FOR PARTS OF
THE WATERS SATURDAY NIGHT INTO SUNDAY IN A TIGHTENING PRESSURE
GRADIENT BETWEEN LOW PRESSURE DEPARTING TO THE NORTH AND HIGH
PRESSURE BUILDING IN FROM THE WEST.

&&

.CLIMATE...

JUST A DAY AFTER RECORD HIGH MINIMUM TEMPERATURES WERE OBSERVED...AN 
EXCEPTIONALLY COLD AIRMASS FOR THIS TIME OF YEAR COULD APPROACH 
RECORD MINIMUM TEMPERATURES EARLY TOMORROW MORNING. BELOW IS A TABLE 
OF RECORD MINIMUM TEMPERATURES FOR APRIL 16 ALONG WITH THE FORECAST 
MINIMUM TEMPERATURE FOR EARLY TOMORROW MORNING.

SITE...PREVIOUS RECORD...FORECAST MINIMUM...
DCA....29 F IN 1928......33 F...............
BWI....30 F IN 1962......31 F...............
IAD....28 F IN 1981......31 F...............

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY 
     MORNING FOR DCZ001.
     FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR DCZ001.
MD...FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY 
     MORNING FOR MDZ004>007-009>011-013-014-016>018.
     FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ011-013-
     014-016>018.
     FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT WEDNESDAY FOR 
     MDZ004>007-009-010.
VA...FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY 
     MORNING FOR VAZ036>040-042-050>057-501-502.
     FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR VAZ052>057.
     FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT WEDNESDAY FOR 
     VAZ036>040-042-050-051-501-502.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT WEDNESDAY FOR 
     ANZ531>534-537-539>541-543.
     GALE WARNING UNTIL 6 AM EDT WEDNESDAY FOR ANZ530>543.
     SMALL CRAFT ADVISORY FROM 6 AM TO 2 PM EDT WEDNESDAY FOR 
     ANZ530-535-536-538-542.

&&

$$
SYNOPSIS...DFH
NEAR TERM...CAS
SHORT TERM...BPP
LONG TERM...DFH
AVIATION...BPP/CAS
MARINE...BPP/CAS
CLIMATE...DFH





National Weather Service
Weather Forecast Office Baltimore/Washington
43858 Weather Service Rd.
Sterling, VA 20166
Phone: (703) 996-2200
Webmaster: lwxwebmaster@noaa.gov
Page last modified: Sep 24, 2008 2:00 PM EDT
Disclaimer
About Us
Credits
Privacy Policy
Career Opportunities
Glossary