197
FXUS61 KLWX 151411
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1011 AM EDT FRI AUG 15 2025
SYNOPSIS
A COLD FRONT CURRENTLY OVER THE VIRGINIA TIDEWATER REGION WILL
CONTINUE NOSING SOUTHWARD INTO THE WEEKEND. SURFACE HIGH
PRESSURE BRIEFLY BUILDS OVERHEAD SATURDAY AND SUNDAY AHEAD OF
ANOTHER COLD FRONT SET TO MOVE THROUGH THE REGION EARLY NEXT
WEEK. THIS FRONTAL ZONE EVENTUALLY STALLS NEARBY.
NEAR TERM /THROUGH TONIGHT/
EARLIER VALLEY FOG IS IN THE FINAL STAGES OF LIFTING. JUST SOME
SCATTERED LOW AND MID CLOUDS EXIST AS OF MID MORNING. THE 12Z
IAD SOUNDING CONFIRMS MODEL FORECASTS OF POOR LAPSE RATES AND
ABUNDANT MID LEVEL DRY AIR. THIS SUPPORTS CAM DEPICTIONS OF
MAINLY ISOLATED COVERAGE OF CONVECTION THIS AFTERNOON. AM NOT
SEEING MANY NECESSARY CHANGES TO THE FORECAST AT THIS TIME.
THE WEAK FRONT IS WELL INTO THE SOUTHEASTERN STATES THIS MORNING.
LIKE TYPICAL SUMMERTIME BOUNDARIES, THE POST- FRONTAL AIR MASS
STILL REMAINS QUITE MILD AND HUMID. GIVEN ELEVATED LEVELS OF
MOISTURE DO NOT GET COMPLETELY SCOURED OUT, A RISK OF ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS EXISTS THIS AFTERNOON AND
EVENING. BASED ON THE 00Z HIGH- RESOLUTION MODEL SUITE, THE
FOCUS SHOULD BE ALONG AND EAST OF U.S. 15, THOUGH MORE RECENT
RUNS HAVE A FEW TERRAIN OR OUTFLOW BASED STORMS AS FAR WEST AS
THE I-81 CORRIDOR. THERE MAY BE A NUMBER OF SLOW MOVING
CONVECTIVE CELLS WHICH IS SUPPORTED BY MULTIPLE FORECAST
SOUNDINGS. MORE SPECIFICALLY, LOW-LEVEL EASTERLIES EXTEND TO
AROUND 800 MB ARE BOUNDED BY WESTERLIES UP TOP WITH A SIMILAR
MAGNITUDE. MOST SHOWERS THAT FIRE UP SHOULD BE POORLY ORGANIZED
WHILE DRIFTING OFF TOWARD THE EAST. AMPLE MID-LEVEL DRY AIR
SHOULD SUPPORT SOME COLD POOL GENERATION, PARTICULARLY IN LIGHT
OF DOWNDRAFT CAPE (DCAPE) VALUES EXCEEDING 1,000 J/KG. SOME
LOCALIZED DAMAGING WINDS CANNOT BE RULED OUT, PARTICULARLY FOR
ANY OF THE TALLER STORMS. MOST SHOWERS SHOULD TAPER OFF AFTER
DARK WITH A DRY NIGHT AHEAD.
TODAY'S TEMPERATURES RETURN TO NEAR AVERAGE WITH HIGHS REACHING
THE UPPER 80S TO PERHAPS AROUND 90 DEGREES IN THE WARMER SPOTS.
WITH DEW POINTS HOLDING STEADY IN THE LOW 70S, THIS WILL CARRY
HEAT INDICES INTO THE MID 90S. POST-FRONTAL EASTERLIES BEGIN TO
WEAKEN INTO THE EVENING AND NIGHT. HOWEVER, THE ONSHORE
COMPONENT TO THE WIND FIELDS MAY INTRODUCE SOME LOW-LEVEL
STRATUS, ESPECIALLY EAST OF THE BLUE RIDGE. OVERNIGHT LOWS FALL
INTO THE UPPER 60S TO LOW 70S, WITH LOW/MID 60S ACROSS MOUNTAIN
LOCALES.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/
THE FRONTAL ZONE WHICH EARLIER SETTLES INTO THE VIRGINIA
TIDEWATER AREA EVENTUALLY TRACKS NEAR THE SOUTHEASTERN U.S.
COAST OVER THE WEEKEND. ATTACHED TO THIS BOUNDARY IS A SLOW
MOVING LOW CENTER WHICH IS EVIDENT ON CURRENT SATELLITE IMAGERY.
WHILE THIS FRONTAL SYSTEM WILL REMAIN THE FOCUS FOR CONVECTION,
SOME ADDITIONAL ACTIVITY IS POSSIBLE OVER THE MID-ATLANTIC
REGION. MAINLY ISOLATED IN NATURE, SUCH SHOWERS WILL LIKELY
FOCUS ALONG AND WEST OF THE BLUE RIDGE AND CATOCTIN MOUNTAINS.
GIVEN A LACK OF ORGANIZATION, THESE SHOULD BE RELATIVELY SHORT
LIVED AND NON-SEVERE IN NATURE. HIGH TEMPERATURES STAY FAIRLY
CLOSE TO THE PREVIOUS DAY, ACCOMPANIED BY CONTINUED EASTERLY
WINDS. IF WINDS TURN LIGHT ENOUGH, SOME ADDITIONAL NIGHTTIME FOG
PRODUCTION IS POSSIBLE. LOW TEMPERATURES WILL BE IN THE
MID/UPPER 60S, WITH SOME LOW 70S ALONG THE I-95 CORRIDOR.
HEADING INTO SUNDAY, MID/UPPER FLOW BEGINS TO TURN MORE
NORTHWESTERLY IN NATURE. THIS IS IN RESPONSE TO HEIGHTS FURTHER
BUILDING OVER THE MISSOURI VALLEY AS THE RIDGE STRENGTHENS.
BASED ON THE GLOBAL ENSEMBLES BOX-AND-WHISKER PLOTS, SUNDAY
COULD PROVE TO BE WARMEST DAY OF THE PERIOD. A NUMBER OF
LOCATIONS MAY REACH 90 TO 93 DEGREES, WITH MID/UPPER 90S HEAT
INDICES GIVEN ELEVATED HUMIDITY LEVELS. SOME ISOLATED SHOWERS
AND THUNDERSTORMS ARE POSSIBLE FOR LOCATIONS ALONG THE
SHENANDOAH VALLEY AND POINTS WESTWARD, AS WELL AS NEAR THE
MASON-DIXON LINE. OVERNIGHT LOWS GO UP BY A COUPLE DEGREES, BUT
REMAIN QUITE SEASONABLE IN NATURE.
LONG TERM /MONDAY THROUGH THURSDAY/
ON MONDAY, OUR REGION WILL SIT BETWEEN A BUILDING UPPER RIDGE TO THE
WEST AND A PRONOUNCED UPPER TROUGH TO OUR NORTHEAST. A SHORTWAVE WILL
PUSH THROUGH DURING THIS TIME ALONG WITH A WEAK FRONTAL PASSAGE,
LEADING TO A FEW SHOWERS AND STORMS AS A RESULT. HIGHS WILL BE BELOW
AVERAGE WITH THE TROUGH NEARBY.
BY MONDAY NIGHT THROUGH THE MIDDLE OF THE WEEK, HIGH PRESSURE WILL
SLIDE BY TO OUR NORTH AND EVENTUALLY OFF THE NORTHEAST COAST. THIS
WILL TURN SURFACE WINDS OUT OF THE NORTH, THEN NORTHEAST, AND
EVENTUALLY EASTERLY AS HIGH PRESSURE BECOMES WEDGED ACROSS THE
REGION. THE OVERALL UPPER-LEVEL PATTERN REMAIN SOMEWHAT LOCKED IN
DURING THIS PERIOD, WITH A FEW WEAK SHORTWAVES SLIDING BY IN NW FLOW
ALOFT. THIS WILL BRING SHOWERS AND A FEW STORMS, WITH THE BEST CHANCE
FOR THUNDER BEING WEST OF I-81, ROUGHLY WHERE THE WESTERN PERIPHERY
OF THE WEDGE BOUNDARY WILL SETUP.
AS WE HEAD TOWARDS THE END OF NEXT WEEK, THE FORECAST REMAINS VERY
UNCERTAIN IN REGARDS TO WHAT IS CURRENTLY TROPICAL STORM ERIN. RIGHT
NOW, A LARGE MAJORITY OF GUIDANCE KEEPS ERIN OFFSHORE, WITH NO
IMPACTS TO THE REGION. ACTUALLY, IF CURRENT GUIDANCE HOLDS TRUE, WE
WILL BE ON THE NORTHWESTERN SIDE OF THE SUBSIDENCE REGION OF THE
STORMS, KEEPING US QUITE DRY. IT IS IMPORTANT TO KEEP UP WITH THE
LATEST UPDATES AT HURRICANES.GOV HOWEVER, AS THE FORECAST CAN CHANGE
AT THIS TIME FRAME. IT IS NEVER A BAD IDEA DURING HURRICANE SEASON
TO PRACTICE YOUR PLAN AND BE READY FOR ONE, SHOULD ACTION BE
NECESSARY IN THE FUTURE.
AVIATION /14Z FRIDAY THROUGH TUESDAY/
HIGH-RESOLUTION MODELS SHOW SOME ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS WHICH MAY IMPACT MANY TERMINALS THIS
AFTERNOON. GIVEN CONTINUED UNCERTAINTY, WILL MAINTAIN PROB30
GROUPS FOR THE THUNDERSTORM RESTRICTIONS DURING THE 19-22Z
TIMEFRAME, THOUGH THIS COULD TREND A FEW HOURS LATER IF OUTFLOWS
CAN CONTINUE TO REGENERATE NEW STORMS. EASTERLY WINDS INTO THE
NIGHT MAY ENCOURAGE SOME LOW- LEVEL STRATUS (MVFR TO IFR) OVER
THE AREA.
FOR THE WEEKEND, ANY CONVECTIVE CHANCES ARE MORE TIED TO THE
TERRAIN. HOWEVER, A FEW OF THESE STORMS COULD AFFECT KCHO OR
KMRB. OTHERWISE, VFR CONDITIONS ARE EXPECTED DURING THE DAYTIME
WITH POTENTIAL PATCHY FOG AT NIGHT. EASTERLY WINDS PERSIST
THROUGH SATURDAY BEFORE TURNING MORE WESTERLY TO FINISH OUT THE
WEEKEND.
SUB-VFR CONDITIONS POSSIBLE AT TIMES MONDAY AND TUESDAY AS SHOWERS
ARE POSSIBLE ACROSS MUCH OF THE AREA. A FEW THUNDERSTORMS ARE
POSSIBLE AT MRB, BUT ELSEWHERE, IT SHOULD BE HARD TO GET THUNDER AS
A WEDGE OF HIGH PRESSURE BUILDS OVER THE REGION, FAVORING LOWER
CLOUDS AND SHOWERS MORE THAN THUNDERSTORMS.
MARINE
BACKGROUND WIND FIELDS STAY BELOW SMALL CRAFT ADVISORY LEVELS
THROUGH THE WEEKEND. AS A FRONTAL ZONE SAGS FURTHER SOUTH TOWARD
THE SOUTHEASTERN U.S. COAST, PREVAILING EASTERLY WINDS ARE
EXPECTED THROUGH SATURDAY WITH GUSTS UP TO 15 KNOTS. EVENTUALLY
WINDS TURN MORE VARIABLE EARLY SUNDAY BEFORE SHIFTING TO
SOUTHERLY. THE MAIN CHANCE FOR ANY THUNDERSTORMS WOULD BE THIS
AFTERNOON BEFORE THE FOCUS SHIFTS WELL TO THE WEST.
WINDS WILL BECOME NORTHERLY BY MONDAY AS A FRONT MOVES THROUGH THE
AREA. THUNDERSTORM CHANCES LOOK TO REMAIN FAIRLY ISOLATED OVER THE
WATERS. EASTERLY WINDS MAY INCREASE TUESDAY, BUT IT REMAINS
UNCERTAIN IF ADVISORIES WILL BE NEEDED. NO THUNDER IS EXPECTED BY
TUESDAY.
TIDES/COASTAL FLOODING
ELEVATED TIDAL ANOMALIES LOOK TO CONTINUE THROUGH THE WEEKEND
GIVEN THE RECENT FULL MOON AND ONSHORE WINDS. ANNAPOLIS MAY
REACH MINOR FLOOD FOR MULTIPLE UPCOMING TIDE CYCLES. WHILE OTHER
LOCATIONS AREN'T CURRENTLY FORECAST TO FLOOD, SOME COULD COME
CLOSE, ESPECIALLY HEADING INTO EARLY NEXT WEEK.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
SYNOPSIS...BRO
NEAR TERM...ADS/BRO
SHORT TERM...BRO
LONG TERM...CJL
AVIATION...ADS/BRO/CJL
MARINE...BRO/CJL
TIDES/COASTAL FLOODING...ADS
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