Thursday, December 31, 2009

Special Statement Update Jan 1 /2010

Time 2:25 PM

Issued: Dec 31/2009 

Currently there is a lull in precipitation across the region. After anywhere from 2.6-3 inches of snow has fallen ..Left over energy is organizing itself over WV and will rotate thru the area this evening and overnight and tap into some atlantic moisture. Snow will once again over spread the area this evening and potentially lay down another 1-3 inches across the region on top of the snowfall that has already occurred. 

This statement covers the PHL burbs all of east central PA into NW NJ into NE PA. 

Due to this Real Weather Services has decided to keep the winter weather advisory in place.  This statement will expire at 7 AM -Jan. 2nd 2010

January 2010 Monthly Outlook


Look for some specifics soon to follow this post..over the next day or two!

Final New Years Eve Storm Map

Wednesday, December 30, 2009

Final Call (Dec. 31/Jan. 1-4) RYAN

Ryan: RWS Team Member

Storm: December 31/Jan 1-Jan 4

Type of Storm: Winter Storm

Format: S/W (1/2)

Scenario: As a S/W developing in the GOM heads NE/NNE into the SE US, it is spreading moisture currently in the form of rain up through the Miss. Valley. This storm will continue on its trek NE delivering Wintry Precipitation into the MA/NE areas. There has been the idea floating around that this is a two wave system. That is correct. The first wave will be the one responsible for most of the accumulations south of NY state. The second wave on the other hand, will track up the EC after coming off of the NC coast and head into Nova Scotia spreading precip into the NNE. After that, there is a likelihood that it will retrograde into the Gulf of Maine spreadin an extended period of SHSN through the NNE/parts of the SNE as well.

Models: Models have been all over the place in the past few days, so the format of forecasting I used for the discussion and analysis is a Nowcast. It seems to be the best way to go. Precip that has developed over the SE which was originally progged to track a bit more to the SE will impact areas in the Mid-Atlantic. This will not be much of a significant storm south of the CONN/RI Area, or for anyone south of NY state.

Areas Affected: MD/DE/PA/NJ/NY/VT/NH/CT/RI/MA/ME

Possible Room for Error: I along with the other members of RWS are watching a potential change in track since this storm was never perfectly depicted on the models. I will update if I see anything suspicious in the radar, steering currents, or water vapor imageries as storms can sometimes deliver surprises.

Headlines: Matt issued a RWS WWA for some areas earlier today.

Maps: I have the overall forecast map and individual state maps for MD/PA.


Timeline (for start of precip):

Washington DC/Baltimore: 3-4 AM Philadelphia: 7AM NYC: 11AM

Boston: Friday Morning(S/W #2)

Hello, I am Ryan and I am a new member of the RWS solutions team from Dundalk, MD. I love the site and am honoreed to be a part of something great.

New Years Eve Snow Potential



Time: 4:10 PM 

Winter Weather Advisory

This winter weather advisory is in place from 12/31/09-1/1/10 


Real Weather Service has issued a Winter Weather Advisory for all of SE PA , All of East Central PA all of Northeast Pa and all of Northwest NJ.

Low pressure currently getting itself organized over the GOM will continue to spread moisture off to the Northeast. This area of low pressure will continue to move off to the NE and be in a position off the delmarva by thursday afternoon. This low pressure will cause overrunning moisture to move into the area after midnight tonight. With surface temperatures around freezing and 850s cold enough ..This should support a mainly snow event across the regions mentioned in this Winter Weather Advisory. 

Early total snowfall accumulations look to be along the range of 2-4 inches. There is a possibility that the area could be looking at more ..however..there is too much uncertainty at this time to hone in on that and this will have to be re addressed with later statements! 

Please stay tuned for any further updates including potential watches and or warnings.

A winter weather advisory is issued when snow/sleet and or freezing rain is expected to impact the region.

Monday, December 28, 2009

Jan 1st-3rd Snowfall Potential


Scenario Map * Will change when first call map is issued 

Friday, December 25, 2009

Christmas Day!


Merry Christmas to everyone!

To the weather its not getting as cold tonight as forecasted to become. Was suppose to go down to 23 degrees but we have only made it down to 27 degrees. Cloudy skies are across the area.

Low pressure is located over eastern missouri...

Radar shows a tremendous amount of moisture associated with this system...

With the warm air aloft basically expecting a total ice scenario versus snowfall at least at the beginning of this system. Ice accumulations will be relatively on the light side with only about .10-.15 but thats enough to make things slippery when traveling. Generally expecting majority of the region to turn over to plain rain.

Thursday, December 24, 2009

Update Scenario for X Mas Day 2009



Questions that still need to be answered...


Temperatures and dewpoints?
Does a secondary form and if so where?
How strong is the high pressure to the north?

However..perhaps the biggest question is how much QPF actually makes it into the region?

I think at this point is the biggest unknown... Not only is how much QPF makes it into the region while the temps are supportive of frozen but how much over all QPF?

How much WAA will there be if the majority of the precipitation rides west of the region and then we are only dealing with QPF from the potential coastal low?

Unfortunately all these might come down to the last couple hours before the event...

On this map I believe Pittsburgh PA will start as brief ice and go to rain and then change back to snow later in the period..same thing stretching up towards Erie Pa...

Tuesday, December 22, 2009

December 25th-27th Storm Potential


Preliminary Scenario Map Subject to change



Friday, December 18, 2009

Unbelievable Satellite Photo of the this Storm!

Photobucket

RWS Issuing A Winter Storm Warning for Dec 19-20

R.W.S  is issuing a Winter Storm Warning for all of SE PA into East Central PA into NW NJ...as well as NE PA. A Winter Storm Warning is issued when a Winter Storm is expected to effect the area within the next 24 hours. 

Low pressure currently over the the Gulf Of Mexico, just south of Louisianna will continue to track off to the NE and end up along the coast of Cape Hatteras. This low pressure, once hitting the gulf stream will deepen and slowly move up the coast. Snow will spread into the region from south to north sometime after midnight. The snow will be heavy at times saturday and saturday night! 

This storm has the potential to deliver a very heavy snowfall across the region. Significant accumulations are expected. 

Current observations show this area of low pressure stronger then modeled and also the precipitation shield further north as well. 

R.W.S will issue a final map early this afternoon after the next model runs come in. Please make plans accordingly. 

This statement was issued at 5:15 AM

Thursday, December 17, 2009

December 19-20th Snow Storm for the Mid Atlantic into the NE


Preliminary Map & I have only issued for MD & North at this point.

The top analogs for this storm are Feb 83, Jan 96 and Feb 03

Monday, December 14, 2009

December 14th Daily Weather Discussion

Since I have the time I am going to resume this. During pre hours of winter storms and during winter storms this will not be updated. Instead see the thread relevant for the weather for those events..

December 14th Daily Weather Discussion

A Potential December to Remember or?
The following have been the high temps at KABE since december 6th to Present

6 34 21 28 -7
7 35 21 28 -7
8 41 26 34 -1
9 40 32 36 2
11 27 16 22 -12
12 37 15 26 -7
13 38 20 29 -4
The last @ in the column is departure from normal. 2nd last # is the average...

Today should be a partly to mostly sunny day once the fog and some clouds move out of the area.

Temperatures will range in the upper 20s to upper 30s in Maine and in the Mid 30s to mid 40s thru out the rest of the region with the exception of south of PA in the lower to mid 50s.

Sunday, December 13, 2009

Dec 13-14th Final Call


Weak low pressure is down along the Tx/ LA border. This low pressure is not very organized nor very strong. The precipitation is out ahead of the low. Commonly called as over running. This over running is essentially being caused by WAA. As this moisture over runs the area majority of the region is at or below freezing and in some cases well below freezing. Currently high pressure is sitting along the east coast which is going to produce a wind out of the south. This WAA is going to cause the 850s to lift above freezing . However for a period of time which i will specify as unknown..the surface will remain below freezing. It just all depends on two things. Surface temperature & how long the CAD can stay in place
The area in Red is primarily going to be ZR and sleet but could start off as a period of snow that could leave a T-1 of show. Further into NE PA potential for an inch or two of snow but even there should end up changing to sleet/ZR..Eventually all areas should change to rain that are in the red zone.

Saturday, December 12, 2009

December 13-14 2009 Rain & Snow!


In between the lines it may start off as frozen depending on how fast the precipitation arrives. However...storm looks to last about 10 hours or less in duration and am expecting a quick transition to rain with the exception of your highest elevations. If the precipitation arrives in fast enough to allow for frozen ..at the most would be looking at T-2 inches.

Things that I was watching last night such as the high pressure..For quite sometime there were two areas of high pressure but that one area no longer exists and the other area is moving east off the coast. The colder scenario would have only existed IF we could have kept both those high pressures in place and moving Northwards.
So essentially expect rainfall with areas along the coast getting .50-1 inch possible
Further inland expect a potential wintry start transitioning to rain with .25-.50 possible

Wednesday, December 9, 2009

Dec 9th SnowStorm Videos

Thus far for the month of December we are 6 inches above normal snowfall in ABE..



Dec 9th-10 Final Update


Just getting around to posting this now



Tuesday, December 8, 2009

December 9-10 Winter Storm


Probably one of the more harder preliminary maps that I have ever had to made for an event. This one took quite a while to make..

Low pressure is currently developing over the SW and that low pressure should continue to move off to the east and eventually turn to the NNE. By wednesday 6 Z this low pressure should be over Southern illinois. Meanwhile another area of low pressure will be riding up the eastern seaboard.

WAA will break out well in advance of this dual low pressure scenario and spread a variety of weather into the region. Anchored to the north of this system will be a high pressure in the range of 1028-1030 mbs and this will provide colder air to anchor in and take hold for awhile. Cold air Damming will effect areas from PA north..however at this point I am not sure if the CAD will be strong enough to reach south of PA. This high pressure will start to lift off to the North and East and as it does so should change precipitation over to all rain in the red zone during the morning on wednesday. The only exception to this will be in the red zone from VT ENE into Maine where it could potentially stay all frozen..

With that all said , before this does changeover to rain its generally going to make the morning rush hour a mess in majority of the NE from PA north.
Again this is preliminary...

Areas not completely sure about are south of PA into western MD..So for those in that area take that part of the map with a grain of salt...

Monday, December 7, 2009

First WideSpread Snowstorm of the 2009-2010 Winter Season

Dec 9th-11th Special Weather Statement

Time 2 PM EST

12/7/09

The following is a special weather statement issued by R.W.S. 


Low pressure currently over the west coast is going to be moving eastward over the next 24-36 hours. This low pressure will be in the ohio valley by about wednesday 12 Z. This low pressure will then move off to the NE but before doing so will develop a secondary over the Chesapeak Bay region. Together these two low pressures will move off to the NE and bring a variety of weather across the region.

This special weather statement applies to all of PA with the exception of SE PA around the PHL area & this also applies to NW NJ.

As the two low pressures move northeast a cold air mass will be in place thanks to high pressure over the northeast. This high will begin to lift into Eastern Canada which will allow this storm to move Northeast. Cold Air Damming will be in place and with precipitation overspreading the area from the south west , look for snow to develop tuesday evening across the areas covered by the statement. The snow may accumulate a few inches before a changeover to ice and then potentially plain rain.

Stay tuned for potential advisories, watches & or warnings on this latest winter storm.

Dec 9th-11th Winter Storm Potential


Alright..here is the scenario map that I mentioned I would put together..

The blue region in PA and southern NY is where you can expect to see snow begin spreading into the area sometime tuesday evening. These areas should mix with and change to ICE potentially before changing to rain on wednesday. Though we will have to see how long the CAD hangs on and should know this better by later this evening. The pinkish/red color is primarily where ICE may occur and could start off as a period of snow..These areas will also change to rain.. The area above the black like is generally where the precipitation should stay all frozen..Primarily snow but its possible that some locations will also change to ICE. This will be clearer later in the evening as well..
Stay tuned for potential Special Weather Statements from R.W.S

Sunday, December 6, 2009

December 6th Daily Weather Discussion

December 6th Daily Weather Discussion

December 4th High temp was 48 degrees @ KABE
December 5th High temp was 40 degrees @ KABE with 3.7 inches of snow

Another storm brewing. Will it be Rain, Ice or Snow or all three?


Today will generally be cloudy to start the day across PA but will be clearing during the day. Further to the north in parts of the Northeast, NY State and north snow showers are still possible and some steadier snow into Maine associated with the low pressure that moved thru yesterday and brought the first pre winter widespread snow storm.
Temperatures will generally be in the 30s to around 40 thru out the region! So if you have any outdoor activities planned..bundle up for its going to be cold.

Saturday, December 5, 2009

R.W.S Winter Weather Advisory

The following is a special weather statement issued by Real Weather Services

12/05/09 2:20 AM

Effective 12/05/09 

Time: 12 noon till 1 AM 12/06/09

The following is a Winter Weather Advisory effective for East Central PA and NW NJ , as well as SE PA. 

Low pressure developing over the Southeast early this morning will continue to lift off towards the North and Northeast and should be in off the Southern New Jersey Coast by 00z Sunday. Precipitation associated with this area of low pressure will start to develop across the southern regions in the early morning hours. Around PHL..it should start out as rain but transition to snow as the day wears on. To the North and West (immediate burbs) there will be a mixture of rain and snow becoming all snow by early afternoon and the far Northern Suburbs should begin as all snow around Noon. Precipitation will begin to taper off by around midnight.

Total accumulations will be in the range of 2-4 inches with some locations receiving as high as 6 inches ..primarily North and West of the city of Philadelphia.

Stay tuned for further updates, watches or warnings if needed!

December 5-6th First Wide Spread Snow Event






Low pressure that is currently over the Southeast in particular the SW Gulf of Mexico is going to basically ride up the eastern seaboard in a projected path of NNE to NE.. to a point where about 06 Z Sunday it will be off the southern New Jersey coast. Since this storm is coming from the GULF area its going to be bringing a good amount of precipitation towards the region. The question becomes how far inland does the precipitation make it?

Taking a look at the latest steering currents ..The first thing that one notices is the high pressure out in the Atlantic..

This tells me that this is not going to allow the developing low pressure to escape too far off to the east as the latest GFS/NAM is showing. It also seems obvious that they are suffering from some convective feedback as well. Its interesting to note that the UKMET @ 00Z has a different story as far as where this low ends up compared to the GFS/NAM. Then again..this is pretty much why within 24 hours we depend more on nowcasting observations then the models themselves.
Looking at the current radar you would think that there was precipitation streaming up the eastern seaboard. However for the most part that is all virga that is streaming up into the area. However..that virga does have one purpose to it as it will help to cool the columns of the atmosphere. This is why its important to keep an eye on your Dewpoints despite where your temps may be because there is going to be dry air to overcome. And with precipitation falling overhead this will help in dropping your temperature closer to its dewpoint. So lets look at our current dewpoints...

As you can see current dewpoints are 30-35 and under across majority of the region so this means that your temps will potentially drop within this range as the precipitation works its way down thru the layers of the atmosphere.
Temperatures generally thru out this event should be in the 30s for most areas with the exception of among the immediate coast and in southern new jersey where I think it will probably be in the lower 40s. That area should see primarily rain but it may end as some flakes of snow.
As this storm rides up the eastern seaboard the one thing that it is going to encounter on its journey is some warm SSTS. This is going to cause the storm to deepen and perhaps quite quickly. I think that some are under estimating the effects of the SSTS on the development of the storm as well as potentially the models. So i think we are looking at a storm somewhere in the range of 990 MBS to 994 MBS.

Like I said looking at the radar one notices the virga..however the other thing that stands out when looking at the radar..

There is two areas of precipitation ..One on the eastern side streaking up the coast (virga up north) and the other on the western side (east of Lousianna) along with moisture streaking northeastward on that western side (again pretty much as virga). However..one question that has to be answered is how about what happens between those two areas of precipitation? Does that area fill in? This is something that is going to have to be watched because this is going to effect the snowfall totals that are being forecasted.
I think that areas will start off as rain along the immediate coast and perhaps in areas like NYC and PHL. However..I think these areas will changeover to snow and the potential is there for 2-4 inches before all is said and done.
On my map I have several different zones labeled ..the areas that start off as rain...will have as mentioned the potential for 2-4 inches of snow but more then likely will verify on the lower end of that range. However..i would not rule out that just outside the city..they could be on the higher end of that range.

So with all that said...here is my final map...One final note is that the yellow area could very easily see up to 6 inches..but for verification purposes have gone with the range of 2-4 but up to 6 inches in that zone would not surprise me.

Friday, December 4, 2009

December 4th Daily Weather Discussion

December 4th Daily Weather Discussion

December 2nd high temp @ KABE was 56 degrees
December 3rd high temp @ KABE was 63
Slipping down & Snow in the forecast?
Today is going to be a mostly sunny day across the region. Overall a pleasant day..perhaps one could say the calm before the storm. In the late evening some high thin clouds will be on the increase.
Temperatures are going to start slipping down with today from yesterdays high temps. Mid 30s to low 40s in Maine..40s along the western side of the Northeast to 50s elsewheres...

Stay tuned for information on the storm up coming

Wednesday, December 2, 2009

November 2009 Verification Map + Original Call



As you know here at Real Wx Services we like to always provide verifications of our monthly outlooks. This was the month of November along with the actual departures.

The overall concept of a relaxation and reloading period was spot on and the overall concept of an above normal November was also correct but the specifics were not warm enough. The seasonal along the western side never occurred as the whole region just torched...

So overall it was not a bad call for the month of November just was not quite warm enough!

December 2nd Daily Weather Discussion

December 2nd Daily Weather Discussion

December first high temperature @ KABE was 44 degrees . This was a negative 1 on the day ..

Colder & Snow in the distant future? After the moderation

Clouds are going to be on the increase today across the region. This is all thanks to low pressure developing over the Southeast around Louisianna. This low pressure is going to move off to the NE and probably cross between Central Pa and western Pa and continue thru Central to western Ny. This is going to put the majority of the region in the warm sector of the storm and also introduce rain into the forecast by late afternoon early evening into PA. By the rest of the evening the rainfall will spread off to the north and east. Now..this low pressure travelling the way it is is important as this helps to usher in some much colder weather. As far as rainfall totals across the region.. Basically looking for 1-2 inches across the region. the higher amounts will be located over Southern New England.
Also since we will be in the warm sector of the storm and there is a powerful cold front that will be issuing in much colder air there is the potential for some stronger thunderstorms across the region with this system. This more then likely occur later in the evening.
Temperatures across the region look to be in the 30s to 40s across maine and then the rest of the region will be in the mid 40s to mid 50s.

Tuesday, December 1, 2009

December 1st Daily Weather Discussion

November 29th high temp @ KABE was 59 degrees
November 30th High temp @ KABE was 49 degrees

Less then 4 days

Today will be pretty much a mixed day of weather across the region. Across portions of the northeast, especially across western sides there will be a chance of scattered rain and snowshowers.These may even occur across the northern tier of PA during the early morning hours. Otherwise to the south of there into the rest of PA and into the eastern side of the Northeast you can generally expect partly cloudy to partly sunny skies across those areas.
Temperatures will generally be in the 30s in Maine to the mid to upper 40s elsewhere with perhaps some lower 50s in southern Jersey and SE PA. To the south of PA temperatures will be in the 50s.