Saturday, January 30, 2010

Winter Stormcast Zone
February 1-15, 2010
Lead Forecaster Ryan K., Sparrows Point High School
Collaborators: Mr. Foot, Brisko, PasadenaMatt, Winterman, Daniel Ross


2:00 PM MONDAY 2.15.2010   Earlier concerns about the clipper rapidly redeveloping once nearing the coast still have merit. For much of the Mid-Atlantic, thankfully recent observations and some computer projections suggest this would not occur until the upper level energy has moved north of the region. Central and Southeastern PA as as the northern I-95 corridor appear to be at greatest risk for significant, if not potentially explosive snow accumulation on Wednesday.

WILL THE FORECAST VERIFY? Below is the team consensus of ideas on what would cause the forecast to verify, or cause it to fail. This will be used to support or reject our forecast hypothesis. Let the chips fall where they may. Be sure to visit our soon-to-be published Storm Data Zone to see the verifiable real numbers behind our forecasts going back to December 18, 2009.

Reasons why our storm grade projections would bust:
1.) The upper level low sweeps all the precipitation out to sea leaving minimal accumulation.
2.) The dry slot overpowers the region.
3.) The storm leaves no shortwaves behind it once it exits off the coast.
Reasons why our storm grade projections would verify:
1.) Upper level low throws back wrap around moisture into the region overnight.
2.) Snow continues into the overnight hours with high ratios causing heavy bands of snow.
3.) The energy transfer occurs while the precipitation is affecting our region.

4:00 PM SUNDAY 2.14.2010  The Forecast Team believes the situation with our Presidents' Day III clipper may changing. A detailed overview of the scenarios we are seeing follows. This information is reposted from the main site earlier today. As reported in the Baltimore Sun today, our team sees one extreme scenario called "Plan C: Coastal?" which could yield up to 12 inches if the right (or wrong!) elements come together, including these three factors playing into Plan C.

Factor 1: The "50/50 low" With almost all of the storms this year, a system will move north of the region and then head into the Canadian Maritimes, however then the storm gets pushed back and retrogrades via the Greenland Block. What this does for us is allows the storms to move up the east coast to some extent, and slows the storms down as well. What is being noticed with our upcoming clipper is that the 50/50 in Canada seems to be retrograding as snow has shown up on radar images this morning.

If this low retrogrades any further, it could significantly impact the outcome of this storm. The storm could be pushed further south then originally expected, providing a more favorable snow track and better precip throughout the region. The 50/50 low could allow much more time for the coastal secondary to get going therefore meaning more snow and a longer duration storm.

Factor 2: Influx of moisture from Gulf of Mexico Originally it was progged by HPC and Sterling NWS that Gulf of Mexico moisture would not be involved in our storm. (The phrase "moisture starved" was used extensively past 2 days.) However, if you check the NWS Watch, Warning, Advisory map, you will notice that there are WWA's and WSW's in the Deep South once again. Models show a plume of moisture from the gulf coast stretching all the way into the Ohio Valley. This precip would juice up the storm and the amounts that occur would be higher in all areas of MD and the rest of the Mid-Atlantic.

Factor 3: Wrap-around snow overnight If the storm was to slow up around our region because of the 50/50 low and blocking in the region than the storm would have time to wraparound snow into our region, with that being another factor that could further raise amounts. The NWS has mentioned the possibility of wraparound in their discussions more than once and it is a legitimate possibility, as it always can be with a developing coastal.

Factor 4: What's nowcasting looking like? The radar imagery as of now as said before has the retrograding precip in Northern Maine which shows signs of a 50/50 being nearby. With our clipper system, the low looks like it wants to go further south then currently modeled, which would then cause the storm to produce more snow for the Mid-Atlantic as well as developing further south meaning the coastal would have more time to hit areas in MD who are not expected to be impacted by the coastal part of the storm.

Written by SPHS Forecaster Ryan K.

10:45 PM SATURDAY 2.13.2010- Here is my map for the upcoming storm. An in depth write up will be completed in the morning when things are nearly locked. There will also be a full region map in my FINAL CALL as usual. 

11:45 AM THURSDAY 2.11.2010 Governor Martin O'Malley let all the people of MD know yesterday that the clean-up efforts will be time consuming and things won't get fully back in place for up to another 60 hours. A positive note is that many streets have already been reached and the efforts continue in full force. 

Our eyes now turn to a small threat Monday Night into Tuesday as a storm system digs into the Lower Mississippi River Valley. The areal forecast discussion from the Sterling NWS doesn't play up the event very much, but that is for good reason. This next storm will not compare to the 3 Historic Storms so far this winter. However, I along with the other members here at Foot's Forecast are paying close attention to the storm for three reasons. One reason is that any snow on top of our monster snowpack would cause problems on an amplified level. Also, the storm if it digs enough has the potential to tap into some moisture influx from the Gulf of Mexico. Finally, the storm has the potential according to an outlet of the NWS to explode off the Mid-Atlantic coast and that could cause heavy snow from DC north. I'll have more as the storm gets closer. 

NEW FEATURE ALERT: Starting next storm, if available I will be doing live updates on the site quite often to keep readers peeled, so be ready for that.
10:45 AM TUESDAY 2.9.2010 Many areas along the I-95 corridor and coastal areas of the Mid-Atlantic could experience 12 hours  or more of near-blizzard conditions late Tuesday night into Wednesday. The team expects strong winds exceeding 30 mph from in Northern Virginia to Boston and west 30 miles from those cities.

Here is where the low will track and where blizzard conditions will be found: 

KAHUNAOPOLIS SNOWFALL  We expect all cities listed below to experience near-blizzard or official blizzard conditions on Wednesday:
Washington DC 11.5 | Baltimore 20.7 | Phila. 21.9 | Trenton 20.6
New York City 19.8 | Hartford 7.4| Providence 6.7 | Boston 4.5

Washington DC: 10-20 Gusts to 30 | Baltimore: 15-25 Gusts to 40
Atlantic City: 25-35 Gusts to 50 | Philadelphia: 20-30 Gusts to 45

Bel Air: 21'' | Elkton: 22.7'' | Olney: 15.3'' | 
| Parole: 16.3'' | Annapolis: 16.9'' | Glen Burnie: 18.4'' |
| Damascus: 15.9'' | Elkridge: 16.1'' | Dundalk: 21.1" | 
| Pasadena: 16.7" | Churchton: 16.1" | Odenton: 16.3'' |
| Manchester: 18.3'' | Fallston: 20" | Parkville: 19.2" |
| Pimlico: 21.1" | Essex: 21'' | Taneytown: 14.9'' | 
| Sykesville: 16.2'' | Columbia: 16.2" | Bowie: 16.1" |
| Leonardtown: 10.8'' | St. Mary's City: 9.9" | Aberdeen: 21.1" |
| Randallstown: 8.3'' | Westminster: 16.6" | Frederick: 14.4" |
| Parkton: 18.9" | Edgewood: 21.9" | Centreville: 11.6" | 


| York: 16.7" | Lancaster: 18.4" | Harrisburg: 17.7" | 
| State College: 9.5" | Reading: 18.3" | Allentown: 17.5" |
| Scranton: 13" | Williamsport: 10.8" | Milford: 17.5" |  
| Hazleton: 19.9" |
| Leesburg: 9.3'' | Alexandria: 9.7" | Fredericksburg: 7.8" |
| Charlottesville: 5.7''| Richmond:2.3'' | Blacksburg: 3.4''| 
| Norfolk: T'' | Virginia Beach: 0'' | King George: 7.9'' |

| Wilmington: 21.8" | Dover: 15.3" | Georgetown: 7.1" |
| Newark: 16.3" | Milford: 10.2" |

| Cherry Hill: 17.5" | Tom's River: 20.2" | Vineland: 19.8" | 
| Cape May: 15.4" | Lakewood: 18.7" |

| White Plains: 13.3" | Newburgh: 4.5" | Monticello: 3.7" | 

Here is my area-wide snowfall accumulations map: 

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