Monday, April 16, 2007

THE APRIL 2007 ULTRAKAHUNA

Now that was taxing...unofficially a barometric low of 969 millibars, or the rough equivalent of a Category 1 Hurricane / strong Tropical Storm. With high wind warnings posted throughout the Mid-Atlantic and Northeast, I wonder if some schools which have not closed or delayed from rain may do so because of wind. Hold a firm grip on that steering wheel.
April 2007 UltraKahuna 969 mb

PREVIOUS POST: Friday evening 4/13. outdoor work/shopping/fun activities done Friday or Saturday. By Sunday morning, the maelstrom will descend on the East Coast and affect fully 1/3 to 1/2 of the Nation's population. Coastal areas will receive a significant lashing of wind, waves and rain while interior sections from Pennsylvania and western Maryland northeastward to Maine may receive their largest snowfall of the season (spring or winter, it's free pick this time.)

April 2007 UltraKahuna Summary

Unfortunately I don't have time to delve into a long-winded analysis of the storm, and you don't have time to read it all anyway, so that's a win-win for both of us. I can say there will be a "sweet spot (or line)" somewhere in Northeast or East Central PA or even western Maryland that is just on the cold sector of this storm, and will receive a whomping amount of heavy wet snow. Just a few miles east or south.. all rain. And plenty of it... consider the latest QPF map for the period Friday to Wednesday:

April 2007 UK - QPF

And finally, Accuweather's Henry Margusity has revised his storm potential map. Again, some may criticize the effectiveness of a "6 to 25 inch" forecast, but the point of this is to give you a general sense of how the storm will affect different regions of the country, not to analyze the accuracy of forecast for an event which has not yet occurred.

April 2007 UltraKahuna revised map

For comparison, below was the first map issued yesterday. Following is copy of the "extended range" discussion from the Hydrometeorological Prediction Center, or HPC. Overall, I think you get the gist of this...a potentially crippling storm will arrive on the East Coast Sunday, and stay until Tuesday or beyond.


April 2007 UltraKahuna

PRELIMINARY EXTENDED FORECAST DISCUSSION

HYDROMETEOROLOGICAL PREDICTION CENTER - CAMP SPRINGS MD - 953 AM THU APR 12 2007 VALID 12Z MON APR 16 2007 - 12Z THU APR 19 2007

...INTENSE STORM FOR EAST COAST SUNDAY INTO MID WEEK...

(MODEL DISCUSSION CUT FOR NOW... WILL POST TOMORROW WITH EDITS)

....EAST...MODERATE TO HEAVY RAINS WILL SPREAD E AND NEWD SUNDAY FROM THE OH VALLEY AND ACROSS THE MID AND S ATLC REGIONS AS LOW PRESSURE MOVES TO THE NC COAST. DEEPENING LOW SUNDAY WILL BRING GALE FORCE SRLY WINDS ALONG THE S ATLC COAST SUNDAY WITH INCREASING NE GALE FORCEWINDS INTO THE MID ATLC. THE LOW WILL BE DEEPENING OFF MID ATLC COASTAL WATERS AND MOVE INTO THE NY BIGHT BRINGING GALE TO STORMFORCE E/NE WINDS INTO NEW ENG/LONG ISLAND WATERS SUNDAY NIGHT INTO MON AND TUES. ABOVE NORMAL SPRING TIDES ASSOCIATED WITH A NEW MOONPHASE / HIGH WINDS AND COASTAL FLOODING ALONG WITH VERY HEAVY TO EXCESSIVE RAIN CAN BE EXPECTED WITH THIS STORM.

INLAND....PCPN TYPE WILL BECOME MORE COMPLICATED AS CONDITIONS SFC AND ALOFT WILL BE COLD ENOUGH FOR SNOW ACROSS INTERIOR PORTIONS OFNEW ENG/NY/PA AND POSSIBLY SWD DOWN THE CENTRAL APPLCHNS. HEAVY SNOW THREAT. HIGH CONFIDENCE FORECAST AND A POTENTIAL HISTORIC EVENT.

SOUTHWARD....THE DEEP STORM WILL BRING STRONG OFFSHORE W-NW WINDS SUNDAY NIGHT THRU MON AND CONTG TUESDAY AND KEEPING UP NW FLOW POSSIBLY INTO THURSDAY IN THE MID ATLC REGION. PROLONGED OFF SHORE FLOW LIABLE TO BRING WELL BELOW NORMAL TIDES CHES BAY/DEL BAY WITHA THREAT OF SOME SOUNDSIDE TIDAL FLOODING NC OUTER BANKS. THIS EVENT HAS SIMILARITY TO EARLY APRIL 1975 BLOWOUT EVENT. THIS AFFECTING SHIPPING IN DEL/CHES BAY HARBORS. A HIGH CONFIDENCE FORECAST. POTENTIALLY HISTORIC EVENT.

PROJECTED PRECIPITATION FOR THE PERIOD FRIDAY 4/13 TO WEDNESDAY 4/18:

April 2007 UK QPF Maps

IF YOU ARE READING THIS BY EMAIL...UPDATES WILL BE POSTED TWICE DAILY STARTING FRIDAY TO SUNDAY. Carefully consider your weekend travel plans if you are going to be along the coast or in the interior and en route back home this coming Sunday.

14 comments:

Mr.B said...

Looks like some fun. MUHAHA

Mr.B said...

Here comes the rain.

Terpboy said...

I'm going to take this opportunity to temporarily hijack this thread, as many of you are loggin on about the U.K.

Anybody in the Baltimore or Harford County vicinity interested in becoming a volunteer weather observer for CoCoRaHS (Community Collaborative Rain, Hail, and Snow observing network) is cordially invited to one of the meetings below.

CoCoRaHS is a national program of volunteer weather observers based out of Colorado State University.

I am the Baltimore County and Harford County coordinator. Leading our meetings will be Bruce Sullivan, the State coordinator, and one of the people who creates those cool maps you see when you go to HPC's website.

Please join us!

Saturday, 5 May

Jarrettsville Library...10 am

Bel Air Library....3 pm


Hope to see you there!

For more info:

http://www.cocorahs.org/

now back to our regularly scheduled programming

Terpboy said...

Seems that the program has reduce me to terpBOY again...???

Mrs. Burke said...

So in basic uneducated terms ... what happens to HarCo and BaCo?

crazedsnowboarder said...

this looks like its going to be a record breaking storm, and also looks like it will drop the same amount of snow that we got all winter

Mr. Foot said...

Mrs. Burke: Basically a whole lot of rain and strong winds will make the first couple days back (for those who have been off this week) unpleasant and stormy up and down the Northeast Corridor.

Mr. B said...

I have a winter storm watch?

E.H. Boston said...

I am going to take my 6" of rain and 60 mph winds like a man...but man oh man would I like to live about 200 miles to the NW....

E.H. Boston said...

With my whopping 43 feet of elevation, I have given up and will now wait until next winter for any type of snowfall.

Mr.B said...

Rain

Mr. Foot said...

Any chance for a delay? High winds up to 50 mph.... problems with the buses. We've gotten out early before for high winds. Whaddya think.

Text of Balt/DC NWS Wind Advisory:

BY MONDAY
MORNING SUSTAINED WINDS OF 20 TO 30 MPH WITH WIND GUSTS TO AROUND
50 MPH ARE EXPECTED. THE STRONG WINDS WILL CONTINUE INTO MONDAY
EVENING BEFORE DIMINISHING.

A WIND ADVISORY MEANS THAT WINDS OF 35 MPH ARE EXPECTED. WINDS
THIS STRONG CAN MAKE DRIVING DIFFICULT...ESPECIALLY FOR HIGH
PROFILE VEHICLES. USE EXTRA CAUTION.

crazedsnowboarder said...

We came close to being pushed off the road by wind on our way to York in the school bus this morning. My house so far has gotten 50mph winds by the time that I left and I expect that to increase. The outside temp was 41 all night but with wind chill added in it felt like 25

Misty said...

ra