Heads UP! Sunday morning updated…. rain Sunday, Storm for Thursday/Friday

Sunday morning update…..
Starts as all rain – and when the rain starts, it will get moderate to heavy quickly!
Still a question at the end of the storm for lower Hudson Valley for a change to snow….
In the NWS’ words….
NEXT QUESTION IS WHAT TYPE THE PRECIP WILL END AS ESPECIALLY IN THE
LOWER HUDSON VALLEY. MODELS SINCE LAST NIGHT HAVE WARMED ALONG WITH
PRECIP ENDING A BIT QUICKER. THIS LENDS TO AN END AS A RAIN/SNOW
MIX…MAY NOT EVEN SEE FREEZING RAIN AS PROFILES SHOW PRECIP ENDING
BEFORE THE SURFACE CAN COOL TO FREEZING. ONLY ISSUE WILL BE IF THE
TEMPERATURE PROFILES COOL A DEG OR TWO AS IT CHANGES TO SNOW WHICH
COULD RESULT IN HEAVY WET SNOW. NOT CONFIDENT ON THIS AT THIS TIME
AND WILL KEEP SNOW TOTALS TO A MINIMUM. OTHER AREAS WILL SEE RAIN
THE ENTIRE EVENT. CURRENT THINKING IS THAT PRECIP SHOULD BE OUT OF
THE AREA BY 6-8Z [1am to 3am]MONDAY.

The National Weather Service is going with a soaking rain for the NYC area for Sunday. There may be some snow at the beginning Sunday morning if it gets cold enough.
Inland could see some snow at the end if the cold air gets here before the heavy rain ends Sunday evening.

Then on Tuesday, the temperature barely makes it to freezing, followed by below freezing temperatures the rest of the week.

The NYC area stays in the deep freeze as a storm gets lined up offshore later in the week. On Thursday and Friday, the area is likely to get snow, but the question is – how much?

But the upper air impulses that will line up to make this a significant storm are forecast to line up far enough off shore to keep the heaviest precipitation offshore and keep the snow amounts low.

In any case, it looks like we’ll stay cold before and after the storm.

Stay tuned.
Here’s the words of the National Weather Service….
WHILE THE CONFIDENCE HAD BEEN HIGH OF PRECIPITATION OCCURRING
SUNDAY…THE EXACT FORM OF PRECIPITATION…MAINLY OVER INTERIOR
REGIONS…HAD BEEN THE UNCERTAIN FACTOR IN THE FORECAST. 12Z
MODELS GENERALLY AGREEING ON THE CENTER OF THE COASTAL LOW MOVING
OVER LONG ISLAND AROUND 00Z MONDAY…THEN SWINGING ON UP INTO THE
GULF OF MAINE BY MONDAY MORNING. THIS TRACK WOULD RESULT IN
PRIMARILY A RAIN EVENT FOR THE MAJORITY OF THE AREA.
BUFKIT
SOUNDINGS FOR INLAND HUDSON RIVER VALLEY DO HINT AT A BRIEF PERIOD
OF RAIN/SNOW MIX RIGHT AT THE ONSET OF THE PRECIPITATION SUNDAY
MORNING…WITH A QUICK CHANGE OVER TO ALL RAIN BY 18Z. SO WILL
HAVE THE MIX MENTION JUST THERE…THEN ALL RAIN SUN AFTERNOON INTO
SUN EVENING. GENERAL CONSENSUS BRINGS PRECIPITATION IN AROUND
14/15Z…WITH THE HEAVIEST PRECIPITATION THEN BETWEEN 18Z-03Z. NO
SNOW ACCUMULATION EXPECTED DURING THE DAY SUNDAY.

NOW…THE MOST QUESTIONABLE TIME BECOMES SUNDAY EVENING BETWEEN
00-03Z [7-10pm] AND WHETHER THE PRECIPITATION REMAINS ALL RAIN…OR
MIXES/TRANSITIONS TO SNOW FOR A PERIOD. THE 12Z MODEL RUNS DID
COME IN SLIGHTLY WARMER…WITH SOUNDINGS ENDING THE PRECIPITATION
AS RAIN EVERYWHERE. DO MAINTAIN THE CONFIDENCE THAT NYC
METRO…LONG ISLAND…AND MOST OF SOUTHERN CT WILL REMAIN RAIN.
MUCH LESS CONFIDENCE WITH WHAT HAPPENS OVER THE LOWER HUDSON RIVER
VALLEY AND EVEN OVER INTO NORTHERN FAIRFIELD COUNTY. WHILE THE
GUIDANCE SUGGESTS IT STAYS ALL RAIN…JUST A COUPLE DEGREE
DIFFERENCE COULD SEE A COMPLETELY DIFFERENT SCENARIO. AND AS THE
MAIN UPPER LEVEL ENERGY PULSES THROUGH AROUND 00Z…THE POTENTIAL
EXISTS FOR ONE LAST BURST OF HEAVIER PRECIPITATION. AS SUCH…HAVE
A PERIOD OF RAIN/SNOW MIX SUNDAY EVENING…WITH SOME AREAS EVEN
TURNING TO ALL SNOW BRIEFLY. ALSO CONTINUED TO INCLUDE LOW
SNOWFALL TOTALS…GENERALLY LESS THAN HALF AN INCH…WITH ISOLATED
AREAS UP TO AN INCH. WITH THE MAIN UPPER LEVEL ENERGY EXITING BY
06Z MON…HAVE TAPERED POPS OFF FROM WEST TO EAST FAIRLY QUICKLY
FOR THE SECOND HALF OF THE NIGHT. THIS SHOULD HELP IN MINIMIZING
THE THREAT OF ANY FREEZING RAIN.

.LONG TERM /MONDAY THROUGH SATURDAY/…
. . . .

12Z MODELS ARE COMING INTO BETTER AGREEMENT REGARDING THE
POTENTIAL OF A COASTAL STORM AFFECTING US THURSDAY INTO FRIDAY.
ALTHOUGH FULL PHASING OF NORTHERN AND SOUTHERN STREAMS ARE STILL
FORECAST TO OCCUR TO OUR EAST…A SHARPENING LONGWAVE TROUGH
STARTS TO BECOME NEGATIVELY TILTED AS ITS AXIS IS NEAR US. THIS
WILL HELP STRENGTHEN LOW PRESSURE EMERGING OFF THE MID-ATLANTIC
COAST SOMETIME LATE THURSDAY/THURSDAY NIGHT. MODELS HAVE THE
CENTER OF THIS STORM EVENTUALLY PASSING NEAR THE 40N/70W BENCHMARK
LATE THURSDAY NIGHT BEFORE HEADING FARTHER NE ON FRIDAY. WITH HIGH
PRESSURE OVER THE VICINITY OF NORTHERN NEW ENGLAND…ANTECEDENT
COLD AIR WOULD HAVE ANY PRECIP BEGIN AS SNOW…AND DEPENDING ON
THE EVENTUAL TRACK OF THE STORM…THIS HAS THE POTENTIAL TO BE AN
ALL-SNOW EVENT. BEST CHANCES FOR ANY MIXING AS USUAL WILL BE OVER
SE SECTIONS OF THE CWA. NOT ENOUGH CONFIDENCE AT THIS TIME IN THE
TIMING/TRACK/STRENGTH OF THE STORM FOR A MENTION IN THE HWO. WOULD
FIRST LIKE TO SEE SOME RUN-TO-RUN CONSISTENCY FOR EACH MODEL AS
WELL AS CONSISTENCY AMONG THE DIFFERENT MODELS.
ADDING TO THE
UNCERTAINTY IS THAT BOTH THE 12Z ENSEMBLE MEAN FOR THE ECMWF…AND
NOT SURPRISINGLY FOR THE GFS…ARE FARTHER SOUTHEAST WITH THE
TRACK OF THE STORM. HIGH PRESSURE WOULD THEN BUILD BEHIND THE
DEPARTING STORM FRIDAY NIGHT AND SATURDAY WITH DRY WEATHER AND
BELOW-NORMAL TEMPERATURES.

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