Severe Thunderstorm Watch

A severe thunderstorm watch has been issued for parts of MD, the Mid-Atlantic and the Northeast.

Here is the SPC message:

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 644
NWS STORM PREDICTION CENTER NORMAN OK
120 PM EDT FRI JUL 31 2009

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

WESTERN CONNECTICUT
DISTRICT OF COLUMBIA
DELAWARE
MARYLAND
NEW JERSEY
SOUTHERN NEW YORK
EASTERN PENNSYLVANIA
NORTHERN VIRGINIA
COASTAL WATERS

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 120 PM UNTIL 900
PM EDT.

HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80
STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES EAST
NORTHEAST OF POUGHKEEPSIE NEW YORK TO 15 MILES WEST OF PATUXENT
RIVER MARYLAND. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

DISCUSSION...MESSY EVOLUTION OF THUNDERSTORMS TODAY AHEAD OF BROAD
UPPER TROUGH AND ASSOCIATED SURFACE COLD FRONT. PREFRONTAL AIR MASS
IS VERY MOIST...ALMOST TROPICAL...AND WILL BECOME MARGINAL TO
MODERATELY UNSTABLE THIS AFTERNOON. SHEAR WILL BE FAIRLY STRONG AND
SUPPORT SUPERCELLS AND LINES OF STRONGER STORMS...WITH PRIMARY
THREATS OF DAMAGING WINDS/HAIL WITHIN NEARLY UNIDIRECTIONAL WIND
PROFILES. HOWEVER...LOW LEVEL SHEAR WILL BE SUFFICIENT FOR AN
ISOLATED TORNADO WITH ANY PERSISTENT SUPERCELL. HEAVY RAINFALL WILL
BE AN ADDITIONAL HAZARD THROUGH THE EVENING.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
MOTION VECTOR 25030.


...EVANS

Hazard Tornadoes EF2+ Tornadoes
Likelihood Low Low
Severe Wind 65 kt+ Wind
Moderate Moderate
Severe Hail 2"+ Hail
Moderate Low


Note: See the experimental Public Watch (SEL) product with explicit hazard information section below. The expiration time in the watch graphic is amended if the watch is replaced, cancelled or extended.
Note: Click for Watch Status Reports.

SEL4
0-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 644
NWS STORM PREDICTION CENTER NORMAN OK
120 PM EDT FRI JUL 31 2009

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

WESTERN CONNECTICUT
DISTRICT OF COLUMBIA
DELAWARE
MARYLAND
NEW JERSEY
SOUTHERN NEW YORK
EASTERN PENNSYLVANIA
NORTHERN VIRGINIA
COASTAL WATERS

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 120 PM UNTIL 900
PM EDT.

SCATTERED DAMAGING WINDS
ISOLATED WIND GUSTS TO 70 MPH POSSIBLE
WIDELY SCATTERED LARGE HAIL TO 1.5 INCHES IN DIAMETER
ISOLATED TORNADOES

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80
STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES EAST
NORTHEAST OF POUGHKEEPSIE NEW YORK TO 15 MILES WEST OF PATUXENT
RIVER MARYLAND. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

DISCUSSION...MESSY EVOLUTION OF THUNDERSTORMS TODAY AHEAD OF BROAD
UPPER TROUGH AND ASSOCIATED SURFACE COLD FRONT. PREFRONTAL AIR MASS
IS VERY MOIST...ALMOST TROPICAL...AND WILL BECOME MARGINAL TO
MODERATELY UNSTABLE THIS AFTERNOON. SHEAR WILL BE FAIRLY STRONG AND
SUPPORT SUPERCELLS AND LINES OF STRONGER STORMS...WITH PRIMARY
THREATS OF DAMAGING WINDS/HAIL WITHIN NEARLY UNIDIRECTIONAL WIND
PROFILES. HOWEVER...LOW LEVEL SHEAR WILL BE SUFFICIENT FOR AN
ISOLATED TORNADO WITH ANY PERSISTENT SUPERCELL. HEAVY RAINFALL WILL
BE AN ADDITIONAL HAZARD THROUGH THE EVENING.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
MOTION VECTOR 25030.


...EVANS

Hazard Tornadoes EF2+ Tornadoes
Likelihood Low Low
Severe Wind 65 kt+ Wind
Moderate Moderate
Severe Hail 2"+ Hail
Moderate Low


SEL4
0-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 644
NWS STORM PREDICTION CENTER NORMAN OK
120 PM EDT FRI JUL 31 2009

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

WESTERN CONNECTICUT
DISTRICT OF COLUMBIA
DELAWARE
MARYLAND
NEW JERSEY
SOUTHERN NEW YORK
EASTERN PENNSYLVANIA
NORTHERN VIRGINIA
COASTAL WATERS

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 120 PM UNTIL 900
PM EDT.

HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80
STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES EAST
NORTHEAST OF POUGHKEEPSIE NEW YORK TO 15 MILES WEST OF PATUXENT
RIVER MARYLAND. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

DISCUSSION...MESSY EVOLUTION OF THUNDERSTORMS TODAY AHEAD OF BROAD
UPPER TROUGH AND ASSOCIATED SURFACE COLD FRONT. PREFRONTAL AIR MASS
IS VERY MOIST...ALMOST TROPICAL...AND WILL BECOME MARGINAL TO
MODERATELY UNSTABLE THIS AFTERNOON. SHEAR WILL BE FAIRLY STRONG AND
SUPPORT SUPERCELLS AND LINES OF STRONGER STORMS...WITH PRIMARY
THREATS OF DAMAGING WINDS/HAIL WITHIN NEARLY UNIDIRECTIONAL WIND
PROFILES. HOWEVER...LOW LEVEL SHEAR WILL BE SUFFICIENT FOR AN
ISOLATED TORNADO WITH ANY PERSISTENT SUPERCELL. HEAVY RAINFALL WILL
BE AN ADDITIONAL HAZARD THROUGH THE EVENING.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
MOTION VECTOR 25030.


...EVANS

Hazard Tornadoes EF2+ Tornadoes
Likelihood Low Low
Severe Wind 65 kt+ Wind
Moderate Moderate
Severe Hail 2"+ Hail
Moderate Low


Note: Click for Watch Status Reports.

WOUS64 KWNS 311715
WOU4

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 644
NWS STORM PREDICTION CENTER NORMAN OK
120 PM EDT FRI JUL 31 2009

SEVERE THUNDERSTORM WATCH 644 IS IN EFFECT UNTIL 900 PM EDT
FOR THE FOLLOWING LOCATIONS

CTC001-003-005-007-009-011-013-010100-
/O.NEW.KWNS.SV.A.0644.090731T1720Z-090801T0100Z/

CT
. CONNECTICUT COUNTIES INCLUDED ARE

FAIRFIELD HARTFORD LITCHFIELD
MIDDLESEX NEW HAVEN NEW LONDON
TOLLAND


DCC001-010100-
/O.NEW.KWNS.SV.A.0644.090731T1720Z-090801T0100Z/

DC
. DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE

DISTRICT OF COLUMBIA


DEC001-003-005-010100-
/O.NEW.KWNS.SV.A.0644.090731T1720Z-090801T0100Z/

DE
. DELAWARE COUNTIES INCLUDED ARE

KENT NEW CASTLE SUSSEX


MDC003-005-009-011-013-015-017-021-025-027-029-031-033-035-037-
041-510-010100-
/O.NEW.KWNS.SV.A.0644.090731T1720Z-090801T0100Z/

MD
. MARYLAND COUNTIES INCLUDED ARE

ANNE ARUNDEL BALTIMORE CALVERT
CAROLINE CARROLL CECIL
CHARLES FREDERICK HARFORD
HOWARD KENT MONTGOMERY
PRINCE GEORGES QUEEN ANNE'S ST. MARYS
TALBOT


MARYLAND INDEPENDENT CITIES INCLUDED ARE

BALTIMORE CITY


NJC001-003-005-007-009-011-013-015-017-019-021-023-025-027-029-
031-033-035-037-039-041-010100-
/O.NEW.KWNS.SV.A.0644.090731T1720Z-090801T0100Z/

NJ
. NEW JERSEY COUNTIES INCLUDED ARE

ATLANTIC BERGEN BURLINGTON
CAMDEN CAPE MAY CUMBERLAND
ESSEX GLOUCESTER HUDSON
HUNTERDON MERCER MIDDLESEX
MONMOUTH MORRIS OCEAN
PASSAIC SALEM SOMERSET
SUSSEX UNION WARREN


NYC005-027-047-059-061-071-079-081-085-087-103-111-119-010100-
/O.NEW.KWNS.SV.A.0644.090731T1720Z-090801T0100Z/

NY
. NEW YORK COUNTIES INCLUDED ARE

BRONX DUTCHESS KINGS
NASSAU NEW YORK ORANGE
PUTNAM QUEENS RICHMOND
ROCKLAND SUFFOLK ULSTER
WESTCHESTER


PAC011-017-025-029-045-077-089-091-095-101-010100-
/O.NEW.KWNS.SV.A.0644.090731T1720Z-090801T0100Z/

PA
. PENNSYLVANIA COUNTIES INCLUDED ARE

BERKS BUCKS CARBON
CHESTER DELAWARE LEHIGH
MONROE MONTGOMERY NORTHAMPTON
PHILADELPHIA


VAC013-047-059-061-099-107-113-137-153-157-177-179-510-600-610-
630-683-685-010100-
/O.NEW.KWNS.SV.A.0644.090731T1720Z-090801T0100Z/

VA
. VIRGINIA COUNTIES INCLUDED ARE

ARLINGTON CULPEPER FAIRFAX
FAUQUIER KING GEORGE LOUDOUN
MADISON ORANGE PRINCE WILLIAM
RAPPAHANNOCK SPOTSYLVANIA STAFFORD


VIRGINIA INDEPENDENT CITIES INCLUDED ARE

ALEXANDRIA FAIRFAX FALLS CHURCH
FREDERICKSBURG MANASSAS MANASSAS PARK


ANZ330-335-338-340-345-350-353-355-430-431-450-451-452-453-454-
455-530-531-532-533-534-535-536-537-010100-
/O.NEW.KWNS.SV.A.0644.090731T1720Z-090801T0100Z/

CW

. ADJACENT COASTAL WATERS INCLUDED ARE

LONG ISLAND SOUND EAST OF NEW HAVEN CT/PORT JEFFERSON NY

LONG ISLAND SOUND WEST OF NEW HAVEN CT/PORT JEFFERSON NY

NEW YORK HARBOR

PECONIC AND GARDINERS BAYS

SOUTH SHORE BAYS FROM JONES INLET THROUGH SHINNECOCK BAY

MORICHES INLET NY TO MONTAUK POINT NY OUT 20 NM

FIRE ISLAND INLET NY TO MORICHES INLET NY OUT 20 NM

SANDY HOOK NJ TO FIRE ISLAND INLET NY OUT 20 NM

DELAWARE BAY WATERS NORTH OF EAST POINT NJ TO SLAUGHTER BEACH DE

DELAWARE BAY WATERS SOUTH OF EAST POINT NJ TO SLAUGHTER BEACH DE

COASTAL WATERS FROM SANDY HOOK TO MANASQUAN INLET NJ OUT 20 NM

COASTAL WATERS FROM MANASQUAN INLET TO LITTLE EGG INLET NJ OUT 20
NM

COASTAL WATERS FROM LITTLE EGG INLET TO GREAT EGG INLET NJ OUT 20
NM

COASTAL WATERS FROM GREAT EGG INLET TO CAPE MAY NJ OUT 20 NM

COASTAL WATERS FROM CAPE MAY NJ TO CAPE HENLOPEN DE OUT 20 NM

COASTAL WATERS FROM CAPE HENLOPEN TO FENWICK ISLAND DE OUT 20 NM

CHESAPEAKE BAY NORTH OF POOLES ISLAND MD

CHESAPEAKE BAY FROM POOLES ISLAND TO SANDY POINT MD

CHESAPEAKE BAY FROM SANDY POINT TO NORTH BEACH MD

CHESAPEAKE BAY FROM NORTH BEACH TO DRUM POINT MD

CHESAPEAKE BAY FROM DRUM POINT MD TO SMITH POINT VA

TIDAL POTOMAC FROM KEY BRIDGE TO INDIAN HEAD MD

TIDAL POTOMAC FROM INDIAN HEAD TO COBB ISLAND MD

TIDAL POTOMAC FROM COBB ISLAND MD TO SMITH POINT VA

ATTN...WFO...OKX...LWX...PHI...ALY...BOX...




Hazard Tornadoes EF2+ Tornadoes
Likelihood Low Low
Severe Wind 65 kt+ Wind
Moderate Moderate
Severe Hail 2"+ Hail
Moderate Low


Note: The Aviation Watch (SAW) product is an approximation to the watch area. The actual watch is depicted by the shaded areas.

SAW4
WW 644 SEVERE TSTM CT DC DE MD NJ NY PA VA CW 311720Z - 010100Z
AXIS..80 STATUTE MILES EAST AND WEST OF LINE..
40ENE POU/POUGHKEEPSIE NY/ - 15W NHK/PATUXENT RIVER MD/
..AVIATION COORDS.. 70NM E/W /22WSW BDL - 38SSE DCA/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 450. MEAN STORM MOTION VECTOR 25030.

LAT...LON 41847161 38277522 38277816 41847472

THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU4.


Watch 644 Status Report Message has not been issued yet.

Quick Update

Ryan with a 330 AM update. As i am in my room, i see the sky as partly cloudy. This is just a quick update, but important as instability will play a huge role in the severe threat. Both Nick and I will both have updates later in the morning, so stay tuned.

SPC Update Out

The SPC Update for today is out and is conservative for the MD area as it has 2% tornado, 15% wind and 15% hail. Thunderstorms to begin with will be there with the thunder probabilities over 90% in our region. The main threat tomorrow will be damaging winds with linear storms and line segments are possible causing the straight line wind damage. The severe weather parameters for tomorrows event are there with the main item, the CAPE around 1500 for the area, the LI values between -3 and -4 for the area, the SWEAT values are around 400, Another threat in my opinion is Flash Flooding and wet microburts as the PWAT values are around 2 for the MD/VA area. The BRN, an index for shear is also around 15-17 for our area, almost perfect for the region. The big question about tomorrows severe weather will be cloud cover, which was a problem in Wednesday's event limiting severe weather. Hail is marginally possible with the mid-level favorability not really where it is needed in terms of web-bulb temps. Finally, Isolated Tornadoes are possible due to the bulk shear being between 30-50kts both in the low and mid levels.

So, for a wrap, the main factor, with all the parameter's in place in sunlight, and the unstable, moist atmosphere is ready to fire with its warm temps, high relative humidities, and high dew points.

Here are my maps:

7/31/09 Severe Weather Discussion/Forecast

Friday 7/31/09 Day 1 Outlook

Tomorrow could be a very active day for parts of Mid Atlantic if the atmospheric conditions and parameters corroperate. This day could be very interesting in severe weather and if we get the right conditions, this could be a great severe weather event for us. The 00z GFS has CAPE values of 500-2000 over portions of the Mid Atlantic, LI values of -2 to -6 over portions of the Mid Atlantic, and 500mb shear of 35 to 55 over most of the Mid Atlantic and Northeast. The 00z NAM has CAPE values of 500-1500 over portions of the Mid Atlantic, LI values of -2 to -5 over portions of the Mid Atlantic, and 500 mb Shear of 30 to 60 over most of the Mid Atlantic and Northeast. The culprit is a front that is going to move up toward our area, bringing us rainfall and potential severe weather. Temperatures will be in the 80s near the coast and the major cities, it could be nearing 90 on the MD/VA coasts, while inland will have temperatures in the 70s because of them having more cloud cover. The coastal areas back to the Interstate 95 area should wake up to some sunshine possible, hence there will be instability with this, inland instability will be harder to get. Humidity will be ample tomorrow everywhere which means rain and storms will be widespread and could contain a lot of rain in them. For tomorrow, I am about 70% confident in this forecast, the main problems that could go wrong is where the front is and especially how much cloud cover is there in the morning. I am seeing that the main factor for severe storms will be Shear and that will be helpful for producing thunderstorms. I believe the best threat area will be in a 15% risk zone in the delmarva area, extending into NJ this area will have CAPE of 1000-1500, LI of -3 to -6, and decent 500mb Shear, this zone will have a slight possibility for tornadoes. The 10% zone will consist of CAPE of 500-1000, LI of -2 to -4, and decent 500mb Shear. The 5% zone will consist of CAPE of 0-500, LI of -1 to -4, and decent 500mb Shear. I am expecting more storms forming in a line then Wednesday and a higher MCS potential. So the main threats Tomorrow will be Damaging Winds, Small Hail, with a slight risk of Tornadoes in the Mid Atlantic, and a flood threat for most of the area.

Comments would be appreciated.

Winter 2009-2010 Maps

Winter 2009-2010 Preview Map

A full forecast will be done by Saturday.

Comments Would Be Appreciated.

Friday Severe Weather Outlook

This is Ryan with Friday's Severe Weather Outlook as the SPC has parts of the Mid-Atlantic under a slight risk area with others located in the see text category:


Yellow: High Low End Risk(10%)
Orange: Slight Risk(15%)

More info on this possibility of severe weather later by either me or nick later today.

Winter 2009-2010 Potential Aspects

Overall, next winter I see it being slightly warmer than the Winter of 2008-2009, but with potentially more coastal tracks and snowfall due to a active southern jet stream next winter. With a Moderate El Nino, which could be weak if the warming slow's down, this could produce a pattern for a +PNA next winter.

I will have my first full winter forecast on Saturday.

11PM Update

Hi, I am Ryan and will be a contributor to Nick's Blog and hope that us teaming up will make an even more reliable forecast.

The once strong line of thunderstorms have fizzled out and there are now only a few small storms with occasional thunder and lightning. The NWS Short Term Forecast says this as of 10:15PM: .NOW...
AT 1015 PM EDT...A CLUSTER OF THUNDERSTORMS...EXTENDING FROM
LIBERTYTOWN TO CLARKSBURG...TO WATERFORD...WAS MOVING EAST AT 30
MPH. THE LINE OF SHOWERS AND THUNDERSTORMS WILL AFFECT MUCH OF NORTH
CENTRAL MARYLAND...ALONG THE INTERSTATE 70 CORRIDOR AND OVER INTO
NORTHEASTERN MARYLAND...INCLUDING THE BALTIMORE METROPOLITAN AREA
THROUGH MIDNIGHT.

LOCATIONS SUCH AS UNIONVILLE...FRIENDSHIP...BARNESVILLE...
BEALLSVILLE...MOUNT AIRY...DAMASCUS...CLARKSBURG...WATERSVILLE...
POPLAR SPRINGS AND POOLESVILLE WILL LIKELY BE AFFECTED THROUGH
MIDNIGHT.

OCCASIONAL CLOUD TO GROUND LIGHTNING IS OCCURRING. WIND GUSTS OF 20
TO 30 MPH CAN BE EXPECTED WITH THIS ACTIVITY. HEAVY DOWNPOURS MAY
REDUCE VISIBILITY BELOW A MILE AND CAUSE PONDING OF WATER ON
ROADWAYS.

Now I think Dundalk, Parkville, Carney, Perry Hall, and Baltimore will be affected through 1135, with Essex, Middle River, Chase, and Edgemere will be affected by 1150.

7/29/09 Severe Weather Discussion/Forecast

Wednesday 7/29/09 Severe Weather Outlook

Tomorrow could be a decent day for severe weather across much of the Mid Atlantic and Northeast if the atmospheric conditions and parameters corroperate. The 00z GFS has CAPE values of 500-1500, LI values of -3 to -7, and Shear of 25 to 35 in the area. The 00z NAM has CAPE values of 500-2000, LI values of -3 to -8, and Shear of 25 to 30 in the area. The culprit is a front that is currently in the Mid West area, and this should slowly approach the region Tomorrow and this will spark up Thunderstorms, with some severe across the region. Tomorrow I see highs mainly in the 80s with 70s possible inland, most regions should wake up to mostly cloudy to mostly sunny skies which may be good for instability and daytime heating. Combined with that, I see high humidity Tomorrow which will be the trigger for storms to pop up over the region. I am about 70% confident of this forecast because of the timing and the speed of the front, the atmospheric conditions and parameters, and the amount of sunshine in the morning hours will control how much instability, moisture, and storms we get. Overall, I am predicting the best potential to be from Virginia to Maine as that area will have the best parameters for severe weather, hence I put them in the 10% risk zone. We should have more reports than yesterday across the area. Now what could change is what I stated earlier in the discussion, If the front speed's up quicker than forecasted, I may have to take Kentucky and Ohio out of the 5% zone and put them in the 0% to 5% zone, if there is more instability involved, I may upgrade the 10% area to a 15% area. For the 5% zone, I am expecting CAPE of 500-1000, and LI of 0 to -3, in the 10% zone, I am expecting CAPE of 1000-2000, and LI of -3 to -8. So basically Tomorrow looks like a decent chance for severe weather, and it is mainly responsible from the front. Main risk's Tomorrow will be damaging wind, small hail. and maybe even an isolated tornado. If I see any major changes, I will have a Mid-Day update.

Comments would be appreciated.

7/28/09 Severe Weather Discussion/Forecast

Tuesday 7/28/09 Day 1 Outlook

There is another potential for Severe Weather tomorrow, this will be located mainly in the Mid Atlantic, especially the Eastern part if the atmospheric conditions corroperate. The 00z GFS has CAPE values of 1000-2500, LI values of -2 to -6, and Laspe Rates of 5.5 to 6.5 in that area. The 00z NAM has CAPE values of 500-2000, LI values of -1 to -7, and Laspe Rates of 5.0 to 7.0 in that area. The reason of this severe weather potential is a cold front which will spark up Thunderstorms, some severe in the Mid Atlantic. Tomorrow, we will have Temperatures mainly in the 80s with potential 90s in the Mid Atlantic. Most places should wake up to partly cloudy to sunny skies, which will give off lots of instability and daytime heating making it favorable for severe weather. I also see enough humidity ahead of the front to have potential scattered areas of thunderstorms, and some could contain heavy rainfall. I am 80% confident in this forecast because of most conditions and parameters won't be hard to predict, it just depends on how quick the front moves and how much cloud cover there is. In the highlighted region, I see CAPE values of mainly 1000-2000, LI values of -2 to -6, and Laspe Rates of 5.5 to 6.5. The main threat's with these storms will be Strong Wind, Small Hail, and Heavy Rainfall. I don't see as much severe weather reports than the last few days, but we still may get several if the weather corroperates. If I see any major changes, I will have an updated map as soon as I possibly can during the day Tomorrow. So that is my forecast, Low Risk of severe weather in the Mid Atlantic.

Comments would be appreciated.

7/27/09 Mid-Day Updated Map

Monday 7/27/09 Day 1 Updated Map.

There has been more sunshine this morning than expected and more instability, hence the recreation of this map.

7/27/09 Severe Weather Discussion/Forecast

Monday 7/27/09 Day 1 Outlook.

There is a potential for a decent severe weather threat in the Mid Atlantic and Southern New England tomorrow if the atmosphere corroperates. The 00z GFS has CAPE values of 500-2000 across that area and LI values of -2 to -7. The 00z NAM has CAPE values of 500-1500 and LI values of -2 to -7. So we have a good amount of CAPE and LI avaliable for tomorrow. The factor is that we have a cold front coming through the region. I would defiantly not be suprised to see morning sunshine giving us more instability, combined with Temperatures mainly in the 80s, this should give us a decent chance for severe weather in the Mid Atlantic and Southern New England, and there will once again be ample humidity. Overall, I am only 70% confident in this forecast since the cloud cover in the morning/early afternoon will be hard to predict, so if we have more cloud cover, this will lead to less instability and less of a threat for severe weather. Although if we get less cloud cover than expected, there could be more severe weather. This is the reason why I am not sold on this forecast, I wouldn't be suprised if I had to put a slight risk [15% and up] area. So my thoughts are that the areas highlighted in the map will have CAPE values of 1000-2000 possible and LI values of -3 to -7. All of my thoughts on the potential area of severe weather are shown above, the main threats will be damaging wind and large hail. I may do a mid-day update tomorrow if I see any major changes, otherwise that is it. Basically just a severe weather potential in the Mid Atlantic and Northeast.

Comments would be appreciated.

7/26/09 Final Severe Weather Discussion/Forecast

Sunday 7/26/09 Day 1 outlook.

The latest 00z GFS has CAPE values of 1000-2500 through a good portion of the Mid Atlantic and Northeast and has LI values of -4 to -8. The 00z NAM has CAPE values of mainly 500-2000 across the Mid Atlantic/Northeast and has LI values of -2 to -6. Overall Tomorrow, I am expecting a good chance of severe thunderstorms across the Mid Atlantic and Northeast. With potential sunshine in the beginning of the day, it will cause instability and will fire up storms with enough CAPE and LI, also there will be Temperatures in the 70s/80s in the Mid Atlantic and Northeast and ample humidity around. Overall, the best area for severe weather in my opinion will be in Northeast MD, Eastern PA, Southeast NY, Western MA, Most of CT, NJ, and Northern DE. In those areas, I see potential CAPE values of 1500-2500 and LI values of -4 to -8 while in the other highlighted areas I see CAPE values of 500-1500 and LI values of -2 to -4, so with all of that in mind, here is my final map which is avaliable at the accuweather forums.

7/26/09 Severe Weather Discussion/Forecast 1

Sunday looks like their could be a potential of Severe Thunderstorms in the Mid Atlantic and Northeast, with enough CAPE and LI values also with enough sunshine early in the day with Temperatures in the 70s and 80s, my first map is avaliable at the accuweather forums.

August 2009 Forecast #1

Here is my first forecast for August.

Temperatures-Average in the Mid Atlantic/Northeast/Coastal
Average to Below Average in the Great Lakes/Western Northeast.

Precipitation-Average in the Mid Atlantic/Northeas/Coastal
Average to Above Average in the Great Lakes/Western Northeast.

I will make a full discussion near the end of next week.

First Winter 2009-2010 Thoughts and Forecast

Here is my first forecast for the upcoming Winter with my current thoughts

• Center-Based Moderate El Nino
• Average to Above Average Temperatures
• Near Average Rainfall
• Near Average Snowfall
• Neutral to Positive NAO
• Neutral to Positive AO
• Neutral to Positive PNA
• Negative PDO
• More active Southern Jet Stream then last year
• Potential for more Coastal Storms then last year
• December=Decent chance of Warm/Dry
• January=Decent chance of Warm
• February=Decent chance of Wet/Snowy

These are my current thoughts, I will update this sometime in August.

Comments would be appreciated.

July 21st 2009 Severe Weather Discussion

Here are my thoughts for Severe Weather on the day of Tuesday, July 21st 2009.

Overall, Tomorrow doesn't look like an active day for severe weather, just isolated reports. First off, the CAPE is shown at levels of 500-1000 on the NAM/GFS and LI values of -1 to -4 for most, also we will have lots of cloud cover and hence less instability to work with. Generally, I believe the Mid Atlantic may have the best threat of severe weather Tomorrow due to that area potentially having the most CAPE/LI, otherwise this should mainly be a non severe thunderstorm and rain event for most, I also don't see warm Temperatures at all, highs may only be in the 60s and 70s, so with all of that, my map is avaliable at the accuweather forums.

The main threat's will be strong winds and small hail.

July Pattern Update

Here are my updated thoughts for the rest of the months.

So far, this July, we have been treated with Below average Temperatures due to a persistent Trough that was centered in the Great Lakes/Southeast Canada giving us Below Normal Temperatures, some have said that this may have been caused by the El Nino, and some by believing that this is ''The year without a Summer'' although the latter isn't true, we have had periods of Above average Temperatures this summer so far.

Anyways, for the rest of the July, I am forecasting this to potentially repeat itself and we will go through a Cooler than average rest of the month with periods where the cool will reload and we will get a couple of Average to Above average Temperature days. The CAR that has been talked about may try to move further west at times, but it shouldn't have that much of an affect on us.
Now, on to CPC's forecasts.

First off, the 6 to 10 day period.

This shows Below average Temperatures for the MA/NE.

Next, the 8 to 14 day period.

This shows a more zonal period, Below average Temperatures in the Northeast/New England, near average Temperatures in the Northern Mid Atlantic, and Above average Temperatures in the Southern Mid Atlantic.

Here is the NAO forecast.

This shows a return to near Neutral, which is normal for around average Temperatures.

Here is the AO forecast.

This also shows near Neutral.

So basically, for the rest of the month, I am expecting a Trough at times and I am expecting it to be Zonal at times, hence for the rest of the month I am going for Average to Below average Temperatures.

That is my discussion, comments would be appreciated.

Welcome To Maryland Wx

Hello everyone, my name is Nick and I am starting a blog that deals with weather for the Mid Atlantic and Northeast zones with no Wishcasting or Bittercasting, just reality forecasts.