405
FXUS61 KGYX 201907
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
307 PM EDT WED MAY 20 2026
WHAT HAS CHANGED
INTRODUCED SOME LOW CHANCE POPS IN SOUTHERN NEW HAMPSHIRE AND
FAR SOUTHWESTERN MAINE AS SOME SHOWERS MAY SPARK AS THE FRONT
CLEARS THE COAST TONIGHT, BUT THESE SHOULD BE VERY LIGHT IF THEY
MATERIALIZE AS DRY AIR WILL BE QUICKLY FILLING IN.
KEY MESSAGES
1. AFTER A BRIEF TASTE OF SUMMER, TEMPERATURES WILL BE
RETURNING TO NORMAL THURSDAY AND A BIT BELOW NORMAL THURSDAY
NIGHT. A FROST ADVISORY WILL LIKELY BE NEEDED THURSDAY NIGHT
AWAY FROM THE COAST.
2. HIGH PRESSURE PROVIDES MOSTLY DRY WEATHER FRIDAY INTO
SATURDAY. MOISTURE ATTEMPTS TO PUSH INTO NEW ENGLAND EARLY NEXT
WEEK WHILE HIGH PRESSURE MAY SUPPRESS ANY WET WEATHER UNTIL
SOMETIME SUNDAY NIGHT OR MONDAY.
DISCUSSION
KEY MESSAGE 1 DESCRIPTION...
A COLD FRONT IS CROSSING THE AREA AT THE TIME OF THIS WRITING
WITH SOME SCATTERED SHOWERS. SO FAR THEY HAVE BEEN JUST BEEN
BRIEF DOWNPOURS, BUT WITH SPC MESOANALYSIS SHOWING 500-1000 J/KG
OUT THERE, A RUMBLE OF THUNDER IS NOT OUT OF THE QUESTION.
BEHIND THE FRONT WILL BE QUITE THE AIRMASS CHANGE FROM WHAT WE
HAVE OBSERVED OVER THE PAST TWO AFTERNOONS. MEAN TROUGHING
OVERHEAD WILL LIKELY KEEP CLOUDS LINGERING THROUGH TONIGHT, AND
MAY EVEN KEEP SOME LINGERING SHOWERS IN SOUTHERN NEW HAMPSHIRE
AND FAR SOUTHERN MAINE THE FIRST PART OF THE NIGHT, BUT 850 MB
TEMPERATURES CRASHING BACK DOWN TO THE FREEZING MARK WILL STILL
MAKE FOR A COOL NIGHT. NORTH OF THE MOUNTAINS WHERE CLOUDS CLEAR
OUT FIRST TEMPERATURES SHOULD BE ABLE TO RADIATE DOWN INTO THE
MID- TO UPPER 30S. IN THE FOOTHILLS AND ON THE COASTAL PLAIN
WHERE CLOUDS AND SLIGHTLY WARMER 850 MB TEMPERATURES WILL BE
OVERHEAD, SURFACE TEMPERATURES BOTTOM OUT IN THE MID-40S TO LOW
50S.
NORTHWESTERLY FLOW THAN INCREASES DURING THE DAY THURSDAY
KEEPING 850 MB TEMPERATURES COOL, BUT WITH HIGH PRESSURE
CLEARING SKIES AND THE HIGH MAY SUN ANGLE WE SHOULD STILL BE
ABLE TO WARM UP INTO 60S SOUTH OF THE MOUNTAINS, AND INTO THE
50S TO THE NORTH. HIGH PRESSURE SLIDES OVERHEAD THURSDAY NIGHT
WHICH IS GOING TO LEAD TO EFFICIENT RADIATIONAL COOLING, TAPPING
INTO 850 MB TEMPERATURES IN THE RANGE OF -2 TO 0C. AS USUAL IN
THESE SETUPS, I HAVE BLENDED IN COOLER MOS GUIDANCE TO THE NBM
TO REFLECT THIS. AS A RESULT, THERE IS A POSSIBILITY THAT
NORTHERN NEW HAMPSHIRE AND PORTIONS OF THE WESTERN MAINE
MOUNTAINS MAY FIND THEMSELVES IN A FREEZE WARNING (ALTHOUGH
CURRENTLY IT LOOKS LIKE TIME BELOW FREEZING MAY ONLY LAST AN
HOUR OR TWO), AS THOSE FORECAST ZONES BECOME ELIGIBLE BEGINNING
TONIGHT. AT THE VERY LEAST A FROST ADVISORY WILL BE NEEDED ALONG
WITH INTERIOR ZONES AS WIDESPREAD TEMPERATURES IN THE MID-30S
SEEMS MOST LIKELY WHICH WILL BE CONDUCIVE TO FROST DEVELOPMENT.
THERE IS STILL TIME SO I WILL LET THE NEXT SHIFT TAKE A LOOK AND
DECIDE WHERE TO HOIST THE ADVISORIES. THE COASTAL PLAIN WILL
LARGELY END UP IN THE UPPER 30S AND LOW 40S, PRECLUDING A FROST
THREAT BUT SOME OF THE NORMALLY COOLER SPOTS COULD SEE PATCHY
FROST. BOTTOM LINE IF YOU HAVE SENSITIVE PLANTS YOU'D LIKE TO
KEEP SAFE, THURSDAY NIGHT WILL BE A GOOD NIGHT TO TAKE
PROTECTIVE MEASURES.
KEY MESSAGE 2 DESCRIPTION...
HIGH PRESSURE WILL CREST OVER THE REGION FRIDAY PROVIDING FAIR
WEATHER WITH HIGHS IN THE 60S TO LOW 70S. A SHORT WAVE DIVING
SOUTHEAST ACROSS ATLANTIC CANADA WILL REINFORCE HIGH PRESSURE
OVER THE REGION SATURDAY AS ANOTHER TROUGH LIFTS INTO THE GREAT
LAKES REGION. LATEST AVAILABLE ENSEMBLE GUIDANCE SUGGESTS HIGH
PRESSURE WILL HOLD OFF ANY MOISTURE FROM THE WAVE MOVING THROUGH
THE GREAT LAKES SATURDAY. THIS WILL RESULT IN A MOSTLY DRY DAY
WITH TEMPERATURES IN THE 60S.
DETERMINISTIC AND ENSEMBLE GUIDANCE SUGGEST THAT ADDITIONAL
WAVES MOVING INTO THE GREAT LAKES WILL HELP BUILD A MID LEVEL
RIDGE OVER NEW ENGLAND SUNDAY WITH SURFACE HIGH PRESSURE
CENTERED OFFSHORE. MOISTURE WILL BE ON THE INCREASE SUNDAY WHILE
THE BULK OF ANY MEANINGFUL RAINFALL MAY REMAIN SOUTH AND WEST
OF THE FORECAST AREA. MORE IN THE WAY OF CLOUDS AND STEADY
EASTERLY WINDS WILL KEEP SUNDAY COOLER WITH HIGHS IN THE UPPER
50S TO LOW 60S. ENSEMBLES THEN SUGGEST THE MID LEVEL RIDGE WILL
SHIFT EAST SUNDAY NIGHT INTO MONDAY WITH HIGHEST CHANCES (40-60
PERCENT) FOR RAIN DURING THE HOLIDAY WEEKEND OCCURING ON MONDAY.
CHANCES FOR SHOWERS WILL LINGER INTO TUESDAY WHILE A GENERAL
DRYING AND WARMING TREND SEEM LIKELY INTO THE MIDDLE OF NEXT
WEEK.
AVIATION /19Z WEDNESDAY THROUGH MONDAY/
THROUGH 18Z THURSDAY...WIND GUSTS EASE AFTER 00Z THURSDAY
WITH CONDITIONS REMAINING VFR THROUGH THURSDAY AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: VFR CONDITIONS EXPECTED TO PREVAIL.
FRIDAY: VFR.
SATURDAY AND SATURDAY NIGHT: MAINLY VFR SATURDAY. CLOUDS
INCREASE FROM THE SOUTHWEST AND MAY LOWER TO MVFR ACROSS
SOUTHERN NH WITH LIGHT RAIN SATURDAY NIGHT.
SUNDAY AND MONDAY: PERIODS OF MVFR WITH LOW CIGS AND OCCASIONAL
RAIN.
MARINE
SCA WIND GUSTS AND WAVES IN THE COASTAL WATERS SUBSIDE THIS
EVENING AS A FRONT CROSSES. HIGH PRESSURE BUILDS IN BEHIND THE
FRONT MAKING FOR TRANQUIL CONDITIONS ON THE WATERS THROUGH
THURSDAY NIGHT. WINDS SHIFT AROUND TO NORTHWESTERLY BEHIND THE
FRONT
HIGH PRESSURE SLIDES OVER THE WATERS FRIDAY AND HOLDS THROUGH
SATURDAY. SEAS OF 2-4FT AND LIGHT, VARIABLE WINDS ARE EXPECTED
FRIDAY INTO SUNDAY MORNING. EASTERLY WINDS PREVAIL SUNDAY INTO
MONDAY WHILE WINDS AND SEAS LIKELY REMAIN BELOW SCA THRESHOLDS.
GYX WATCHES/WARNINGS/ADVISORIES
ME...NONE.
NH...NONE.
MARINE...NONE.
DISCUSSION...BARON/SCHROETER
AVIATION...
MARINE...
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