932  
FXUS61 KLWX 271406  
AFDLWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC  
906 AM EST WED JAN 27 2021  
   
SYNOPSIS
 
 
HIGH PRESSURE WILL BRIEFLY RETURN TODAY, BUT AN AREA OF LOW  
PRESSURE WILL GRAZE THE AREA TO THE SOUTH TONIGHT INTO THURSDAY.  
HIGH PRESSURE WILL BRIEFLY RETURN AGAIN FRIDAY INTO SATURDAY  
BEFORE ANOTHER STORM SYSTEM APPROACHES FOR LATE IN THE WEEKEND  
INTO EARLY NEXT WEEK.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
LATEST ANALYSIS DEPICTS A FAIRLY WEAK COLD FRONT PUSHING  
SOUTHEASTWARD AWAY FROM THE REGION. THE 12Z KIAD SOUNDING SHOWS  
A SUBSIDENCE INVERSION WHICH MAY TRAP SOME MOISTURE LEADING TO  
STUBBORN STRATOCUMULUS CLOUDS THROUGH ABOUT MIDDAY. OTHERWISE,  
A BREEZY DAY WITH SOME SUN IS EXPECTED, WITH WARMER TEMPERATURES  
THAN YESTERDAY, BUT SIGNIFICANTLY MORE WIND. GUSTS WILL REACH  
THE 20-30 MPH RANGE, KEEPING WIND CHILL TEMPERATURES IN THE 30S  
ALL DAY LONG.  
 
TONIGHT, LOW PRESSURE CURRENTLY DEVELOPING OVER THE GULF COAST  
WILL HEAD NORTHEAST INTO THE CAROLINAS. HIGH PRESSURE BUILDING  
SOUTHWARD IN THE WAKE OF TODAY'S FRONT WILL HELP KEEP THIS  
SYSTEM SUPPRESSED TO THE SOUTH. MODELS ARE IN GOOD AGREEMENT  
THAT NO PRECIP WILL FALL NORTH OF WASHINGTON DC. HOWEVER, A FAIR  
NUMBER BRING SOME LIGHT SNOW AS FAR NORTH AS DC, AND MORE BRING  
SNOW INTO CENTRAL VA. AT THIS POINT, WILL KEEP CHANCE POPS FOR  
OUR SOUTHERN ZONES AND SLIGHT CHANCE UP TO DC, WITH A LIGHT  
(MAINLY LESS THAN AN INCH) ACCUMULATION FOR CENTRAL VA. DAY  
SHIFT MAY NEED TO ADJUST POPS UPWARD TOWARDS LIKELY IN THIS AREA  
IF THE 12Z SUITE COMES INTO BETTER AGREEMENT ABOUT WHERE THE  
CUT-OFF IN PRECIP WILL BE, BUT AT THIS TIME, NO ADVISORIES ARE  
ANTICIPATED. OTHERWISE, TONIGHT WILL BE COLDER THAN TUESDAY  
NIGHT, WITH LOWS MOSTLY IN THE 20S AND A BRISK NORTHERLY WIND AS  
THE STORM STRENGTHENS AND THE GRADIENT INCREASES.  
 

 
   
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/
 
 
LOW PRESSURE PULLING AWAY OUT TO SEA WILL BE THE MAIN STORY  
THURSDAY AND FRIDAY. ANY LINGERING SNOW SHOULD END EARLY  
THURSDAY MORNING IN OUR SOUTHERN ZONES, BUT WINDS WILL INCREASE  
SIGNIFICANTLY. THERE IS A CHANCE WE MAY NEED WIND ADVISORIES,  
AS GUSTS LOOK LIKELY TO REACH 40 MPH, AND COULD PUSH PAST 45.  
WITH THE RATHER COLD (FOR THIS WINTER) TEMPERATURES, WIND CHILLS  
WILL STAY IN THE TEENS AND 20S ALL DAY LONG AS WELL. OTHERWISE,  
THE CLOUDS SHOULD BREAK FOR SOME SUN AS THE DAY PROGRESSES AND  
HIGH PRESSURE SLOWLY STARTS BUILDING IN.  
 
THE STORM WILL ONLY SLOWLY MOVE AWAY THURSDAY NIGHT THROUGH  
FRIDAY NIGHT, WITH GUSTY WINDS ONLY SLOWLY DIMINISHING THROUGH  
THIS TIME. COLD AIR FROM CANADA WILL ALSO ADVECT SOUTH ACROSS  
THE REGION, WITH THE POTENTIAL FOR SOME OF THE COLDEST DAYS AND  
NIGHTS WE'VE HAD SO FAR THIS WINTER, THOUGH WITH THE LACK OF  
REAL COLD SO FAR THIS YEAR, THIS ISN'T REALLY SAYING MUCH.  
WIDESPREAD TEMPERATURES INTO THE TEENS WOULD HAVE NORMALLY  
HAPPENED BY NOW, AND MAY AT THE END OF THIS WEEK, BUT HAVEN'T  
HAPPENED YET, SO IT COULD BE THE COLDEST OF THE SEASON SO FAR.  
OTHERWISE, DRY CONDITIONS SHOULD PREVAIL.  
 

 
   
LONG TERM /SATURDAY THROUGH TUESDAY/
 
 
HIGH PRESSURE OVERHEAD WILL KEEP US DRY AND CHILLY SATURDAY. AS  
THE NORTHERN FRINGE OF THIS HIGH DEPARTS TOWARD THE NORTHEAST,  
THE SOUTHERN HALF WILL WEDGE ALONG THE EASTERN SLOPES OF THE  
APPALACHIANS. THIS WILL LIKELY KEEP COLD AIR IN PLACE AHEAD OF A  
DEVELOPING LOW PRESSURE SYSTEM THAT COULD BRING US A MIX OF  
RAIN AND SNOW OR ALL SNOW LATER IN THE WEEKEND. CLOUDS WILL  
INCREASE SATURDAY NIGHT BEFORE THICKENING WITH PRECIPITATION  
ARRIVING SUNDAY.  
 
AS OF NOW, THE PRECIPITATION LOOKS TO ARRIVE AS SOME LIGHT SNOW  
LATE SATURDAY NIGHT INTO EARLY SUNDAY FROM SOUTHWEST TO  
NORTHEAST. AS AN EASTERLY FLOW INCREASES AHEAD OF THE MAIN STORM  
SYSTEM, WE THROW A FACTOR OF RAIN INTO THE PRECIPITATION TYPE  
MIXTURE. BY LATE SUNDAY EVENING AND CONTINUING SUNDAY NIGHT AND  
THROUGH MIDDAY MONDAY, THE EASTERLY FLOW GRADUALLY BECOMES MORE  
NORTHERLY. THIS IS DUE TO A COASTAL LOW PRESSURE SYSTEM FORMING  
NEAR THE OUTER BANKS AND INTENSIFYING AS IT MOVES TOWARD THE  
NORTHEAST.  
 
BY MONDAY NIGHT AND INTO TUESDAY, PRECIPITATION SHOULD TAPER  
OFF AND END SLOWLY FROM WEST TO EAST AS THE COASTAL LOW MOVES  
AWAY AND HIGH PRESSURE BECOMES REESTABLISHED IN THE REGION.  
TEMPERATURES WILL BE NEAR AVERAGE DURING THE LIFETIME OF THE  
STORM SYSTEM.  
 

 
   
AVIATION /15Z WEDNESDAY THROUGH SUNDAY/
 
 
VFR CONDITIONS HAVE RETURNED EXCEPT AT KCHO WHERE CONDITIONS  
SHOULD IMPROVE BETWEEN 15Z-16Z. NW WINDS THEN GUST 20-25 KNOTS  
TODAY. TONIGHT, SUB-VFR CONDITIONS MAY REACH CHO WITH SOME SNOW  
MOVING IN FROM THE SOUTH, BUT FURTHER NORTH, THIS IS UNLIKELY.  
ANY SNOW MOVES OUT EARLY FRIDAY. WINDS MAY RELAX A BIT TONIGHT,  
BUT LIKELY INCREASE SUBSTANTIALLY ON THURSDAY WITH GUSTS  
POTENTIALLY APPROACHING 40 KNOTS. SLIGHTLY WEAKER WINDS ON  
FRIDAY, BUT STILL GUSTY.  
 
VFR CONDITIONS SATURDAY AND SATURDAY NIGHT WITH VARIABLE WINDS.  
VFR CONDITIONS TO START SUNDAY MORNING, BUT CONDITIONS SHOULD  
DETERIORATE MIDDAY SUNDAY THROUGH SUNDAY NIGHT WITH  
PRECIPITATION ENCOMPASSING THE REGION. MVFR TO IFR CONDITIONS  
POSSIBLE MIDDAY SUNDAY AND SUNDAY AFTERNOON DUE TO LOWERING  
CEILINGS. WINDS EAST 5 TO 10 KNOTS GUSTS TO 15 KNOTS SUNDAY,  
BECOMING NORTHEAST TO NORTH AROUND 10 KNOTS SUNDAY NIGHT.  
 

 
   
MARINE
 
 
COLD FRONT WILL BRING SCA CONDITIONS TO THE WATERS TODAY. WINDS  
RELAX JUST A LITTLE THIS EVENING, THEN INCREASE AFTER MIDNIGHT  
AND ESPECIALLY AFTER DAWN THURSDAY AS A LOW PRESSURE STRENGTHENS  
OFF THE COAST. THIS LIKELY BRINGS GALES TO PART, IF NOT ALL, OF  
OUR WATERS FOR THURSDAY, POSSIBLY EXTENDING INTO THURSDAY NIGHT.  
WINDS RELAX A BIT FRIDAY AS THE LOW PULLS FURTHER AWAY, BUT SCA  
STILL LIKELY.  
 
NO MARINE HAZARDS EXPECTED SATURDAY AND SATURDAY NIGHT. WINDS  
VARIABLE 5 TO 10 KNOTS. SMALL CRAFT ADVISORIES ARE POSSIBLE  
SUNDAY AND SUNDAY NIGHT. WINDS BECOMING NORTHEAST TO NORTH 10 TO  
15 KNOTS GUSTS UP TO 20 KNOTS.  
 

 
   
LWX WATCHES/WARNINGS/ADVISORIES
 
 
DC...NONE.  
MD...NONE.  
VA...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR VAZ036>039-  
050-051.  
WV...NONE.  
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THURSDAY FOR ANZ531>533-  
539>542.  
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ530-  
535-536-538.  
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EST  
THURSDAY FOR ANZ530-535-536-538.  
SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ534-537-  
543.  
GALE WARNING FROM 6 AM TO 6 PM EST THURSDAY FOR ANZ534-537-543.  
 

 
 

 
SYNOPSIS...RCM  
NEAR TERM...RCM/DHOF  
SHORT TERM...RCM  
LONG TERM...KLW  
AVIATION...RCM/KLW/DHOF  
MARINE...RCM/KLW  
 
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