This is from the National Weather Service national center in DC…..
..”POTENTIAL FOR MAJOR STORM OVER THE MID ATLANTIC & NORTHEAST EARLY NEXT WEEK...”
We’re talking about a storm at least 5 days from its major impact, and in New England, closer to 7 days. But the threat needs to be talked about, due to the large population areas potentially affected AND the consistent forecasts of the world’s most accurate computer model-the EUROPEAN.
As I’ll explain, there are signs in other models that are troubling, as well. Believe me, you do NOT want to see the worst case scenario of this storm. As much as I love storms, this is one I hope stays on the farther east track.
Here’s more from the NWS Extended Discussion from DC:
THEREIN LIES THE STORM'S MENACE- A POWERHOUSE CAPABLE OF WHIPPING
THE ATLANTIC INTO A FRENZY AND CHURNING UP DANGEROUS TIDES. OF
PARTICULAR NOTE IS THE COINCIDENCE OF THE FULL MOON ON SUNDAY,
OFTEN A SIGNIFICANT FACTOR IN HISTORICAL EVENTS. THE OCEAN EFFECTS
OF THE SYSTEM MAY STILL BE REALIZED EVEN IF POST-TROPICAL SANDY
DOES NOT MAKE LANDFALL IN THE UNITED STATES. BESIDES THE WIND, THE
OTHER SENSIBLE WEATHER THREAT IS HEAVY RAINS, WITH HEAVY SNOWS
POSSIBLE ON THE SOUTHWEST SIDE OF THE HYBRID CIRCULATION WHERE
CONTINENTAL POLAR AIR RUSHES ACROSS THE CENTRAL APPALACHIANS.
And from the local Mt. Holly NWS discussion: (IF closer track is right)
WITH A TROPICAL SYSTEM INTERACTING WITH
A SLOW MOVING COLD FRONT...WOULD BRING A FULL WAGON OF ISSUES TO
OUR REGION...INCLUDING HEAVY RAIN...FLASH FLOODING...RIVER AND
STREAM FLOODING...HIGH WINDS...AND TIDAL FLOODING IN THE SUNDAY
THROUGH TUESDAY TIME FRAME.
So you can see the potential for big trouble. Here’s what earned the concern (EURO from 7am Tue):
Yikes! The closer the lines are together, the more intense the storm and the stronger the winds. This would be devastating for New England, and cause big problems around here.
Yesterday, I talked about the Ensembles of the EURO, where the initial conditions are changed a little bit and the model is run 51 times. The Ensembles today show a very close match with the map above. That leads to more confidence that the EURO will at least be close to being right (plus having the same solution 5 times in a row-since Sunday).
But the American model, the GFS, still has a track much farther east. So that’s good, right? Not quite. First, the GFS has a tendency to be too fast and too far east with coastal storms, especially far out in time. And second, many more of the GFS ensembles resemble the EURO than they did yesterday. Here are the maps:
Half of those solutions have a major storm close to the East Coast or actually making landfall at the coast. When I see a long-range forecast with so many ensemble members showing an extreme solution, I tend to forecast in that direction. So, in a way, the GFS is “going for” the storm, too.
Here are the official forecast maps from the NWS:
That’s very close to the EURO solution.
IFFFFFFF that is right, what happens?
1. The East Coast of Florida gets 40+ mph winds and flooding rains
2. The New Jersey/Delaware gets 40+ mph winds, but they are offshore when the wind is strongest. Still, lots of onshore winds ahead of the storm PLUS the full moon will lead to beach erosion and coastal flooding.
3. VERY heavy rain would extend well inland, with a flood threat possible just about anywhere in our area.
4. The worst coastal flooding will occur just east and north of where the storm makes landfall. In this case, that would be from Long Island into New England. But if it makes landfall farther south, the Jersey shore would be in bad shape.
5. On the cold side of the storm (west of the track), cold air will move in with northerly winds, PLUS the atmosphere will cool from aloft down to the surface. This means a threat of at least some snow in PA, perhaps in the mountains, but…..
The worst of the storm around here could be anywhere from Sunday to Tuesday.
Remember, we are still talking about 5-7 days out, PLUS this is a rare event, so we are far from certain about what will happen. Computer models may change in the days to come. If we see the EURO trending farther east and the GFS farther west, we will become more confident of the track. Today is more of a “heads up” on a possible big storm. Actual specific forecasts will come later in the week. And, of course, I’ll write a new blog each day as long as the threat exists.