Historic Nor'easter poised to slam Boston and the Northeast U.S.
A potentially historic Nor'easter is brewing for the Northeast U.S., where blizzard watches are up for much of eastern Massachusetts, Rhode Island, and Connecticut. The storm, dubbed "Nemo" by the Weather Channel, is expected to bring heavy snows of 1 - 2 feet, coastal wind gusts over hurricane force, and moderate to major coastal flooding. During the peak of the storm, Friday night into Saturday morning, snowfall rates of 2 - 3" per hour can be expected. These intense bursts of snow may be accompanied by lightning and thunder. The cites of Boston, Hartford, Providence, Portland, and Burlington are all likely to get more than a foot of snow, and two feet of snow will probably fall along a swath from the western suburbs of Boston to Southwest Maine. With the Nor'easter generating these heavy snows expected to bomb out with a central pressure of 972 - 976 mb, the rapid flow of air around this low pressure center will generate ferocious sustained winds near 50 mph at the coast, with wind gusts in excess of hurricane force--74 mph. The combination of heavy snow and high winds will make travel extremely dangerous or impossible, with near-zero visibility in white-out conditions. Total snowfall from the storm is likely to rank in the top ten for Boston since weather observations began at Logan Airport in 1936. According to NWS, here are the top snowstorms since 1936 for Logan Airport:
1. February 17-18, 2003 27.5"
2. February 6-7, 1978 27.1"
3. February 24-27, 1969 26.3"
4. March 31-April 1, 1997 25.4"
5. January 22-24, 1945 22.8"
6. January 22-23, 2005 22.5"
7. January 20-21, 1978 21.4"
8. March 3-5, 1960 19.8"
9. February 16-17, 1958 19.4"
10. February 8-10, 1994 18.7"
11. January 7-8, 1996 18.2"
11. December 20-22, 1975 18.2"
11. December 26-27, 2010 18.2"
Figure 1. Predicted wind speeds in knots at 7 am EST Saturday, February 9, 2013, from the 00Z February 7, 2013 run of the European (ECMWF) model. The model is predicting sustained winds of 50 knots (57.5 mph) will affect Cape Cod and Nantucket Island, Massachusetts. Multiply by 1.15 to convert knots to mph.
Serious coastal flooding expected in Massachusetts
The high winds from the storm will drive a damaging storm surge of 2 - 4' along the coast of Eastern Massachusetts Friday night and Saturday morning. Of particular concern is the flooding that will occur during the Saturday morning high tide cycle, as that is the time of the new moon, which will bring the highest tide of the month. The ocean's height in Boston varies naturally by about ten feet between low tide and high tide, so it matters greatly when the storm surge arrives, relative to the tidal cycle. Thus we speak of the "storm tide"--how how the water gets above the high tide mark, due to the combination of the storm surge and the tide. During Hurricane Sandy, on October 29, 2012, a potentially very damaging storm surge of 4.57' hit Boston, but arrived near low tide, so the water level during the peak surge did not rise above the normal high tide mark. As of noon EST on February 7, 2013, the latest storm surge forecast from the GFS model is calling for a storm tide of about 3.4' above high tide (MHHW, Mean Higher High Water) on Saturday morning, which would cause only minor flooding in Boston. This would be the 10th highest water level on record in Boston since tide gauge records began in 1921. According to former NHC storm surge expert Mike Lowry, who now works for TWC, the official top 5 storm tides at the Boston tide gauge, relative to MHHW, are:
1. 4.82' - February 7, 1978 (Blizzard of 1978)
2. 3.92' - January 2, 1987
3. 3.86' - October 30, 1991 (Perfect Storm)
4. 3.76' - January 28, 1979
5. 3.75' - December 12, 1992
More serious flooding is expected in Cape Cod Bay to the southeast of Boston, where the northeast winds from the storm will pile up a higher storm surge. A storm surge of 3 - 4' is predicted from Scituate to Sandwich Harbor Saturday morning. The surge will be accompanied by battering waves 20' feet high, and major flooding and coastal erosion is expected. Major coastal flooding is also expected on the east end of Nantucket Island.
Figure 2. Coastal flooding hazards during the high tide cycle on Saturday morning, February 9, 2013, as predicted at 12 pm EDT Thursday, February 7, 2013, by the NWS Boston.
Links:
Our news page
http://www.wunderground.com/news/
Our winter Storm page:
http://www.wunderground.com/winter-storm/nemo-2013.asp
Jeff Masters
Reader Comments
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 — Blog Index
eeeeeeeeeeh....... no.
but geaux sneaux!
that's normal.
it's an extratropical cyclone with a large windfield blowing in from offshore...
but GEAUX SNEAUX!
there is some rain mixing in there so the snow has hard time
Next 48hrs..
All red/max warnings except Providence and Philadelphia..
the snow has grown thin down here...not too much moisture in the air apparently
I actually don't wanna know that...could be deadly
Looks to be 13-15' above normal tides at its highest
Here is the latest HPC analysis:
And here is the latest RAP analysis:
I know the RAP one self-updates, but I'm not sure about the HPC one (I think it does). RAP updates hourly and if HPC updates, it's every three hours.
great thanks... so now down to 994 mb...
My guess is that it won't make it too much further north before the deepening storm begins tapping into the cold air from the banana high. Maybe right to about the Connecticut coastline?
Will that line cut the snowfall totals for NYC?
geaux sneaux? what does that mean? :-/
About so... if not somewhere in the Long Island Sound...
Btw.. I just watch the Accuweather storm video...Bernie Rayno called the NAM worthless...ouch!
Not really. That line is what is keeping the snowfalls totals for NYC to a foot rather than more than a foot. I'm in central New Jersey and am quite glad that the rain/snow line is doing its little dance around me. I've dug out of 2 feet of snow before. It isn't fun.
.NEAR TERM /THROUGH TONIGHT/...
LIGHT SNOW IS DEVELOPING OVERHEAD ACROSS THE REGION AS MOISTURE
BUILDS AND THE TWO SYSTEMS JUST BEGIN TO INTERACT WITH EACH OTHER
BEFORE THEY PHASE. THE SNOW WILL BE LIGHT AT FIRST AND ASSOCIATED
PRIMARILY WITH THE UPPER LEVEL TROF AND WEAK SURFACE LOW MOVING
THROUGH THE GREAT LAKES. WE COULD STILL SEE AN INCH OR TWO BY
SUNSET.
TRENDS IN DATA SUGGEST THE SURFACE LOW MAY BE TRACKING CLOSER TO THE
COAST AS THE CENTER IS JUST WEST OF HATTERAS...AND THE BEST
PRESSURE FALLS ARE JUST EAST OF THE NORTHERN OUTER BANKS. SOME
RAIN HAS BEEN OBSERVED OVER EASTERN LONG ISLAND AND A MIX INTO
PARTS OF NEW YORK CITY. ONCE THE UPPER DYNAMICS STRENGTHEN...A
CHANGEOVER TO SNOW SHOULD OCCUR...BUT THE RAIN/SNOW LINE WILL BE
VERY CLOSE AND COULD WAVER THROUGH THE DAY AND NIGHT DEPENDING ON
WHERE THE STORM EVENTUALLY TRACKS. IF THE RAIN/SNOW LINE SETS UP
ALONG THE COAST OR JUST INLAND...THEN THE HEAVIEST SNOW AXIS WOULD
SHIFT WEST AND NORTH. THE FRONTOGENESIS FORECAST SUGGESTS
YARDSTICKS WILL BE NEEDED TO MEASURE SNOW IN THE AXIS OF HEAVIEST
SNOW...THE NORTHWEST EDGE OF WHICH COULD SPREAD OVER A SLIGHTLY
LARGER PART OF THE FORECAST AREA.
At least indirectly it will. Even if the rain-snow line never makes it north of New York City (which I think it will for a short time period), just being so close to the r/s line means that the snow to liquid ratio won't be so good with relatively warmer air aloft. As long as that r/s line is so close, snowfall to liquid ratios will probably be <10:1, or a very heavy and wet snow.
DISCOUNTED 00Z NAM AND IT/S ASSOCIATED 4 INCH PLUS QPF TOTALS OVER
WESTERN CWA IN NJ.
He may have to eat his words later on..
If he will be a man about it that is..
I don't care for him anyway..
JMO of course..
Cajun ;-) go snow
Viewing: 1001 - 1039
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 — Blog Index