11/06/14 Rain Event

A piece of moisture filled energy in the southeast is going to be picked up by a trough on Thursday and bring a decent amount of rain to the area. Looking at a start time Thursday morning with the heaviest rain in the afternoon. A good .75-1.50 inches of rain can be expected. Sunshine returns on Friday.

Latest on this from NWS, seems they are not sure on how strong this will be, they mentioned windy conditions last night, have since not noted that. Models show it could get quite windy, especially with passage.

MAIN FEATURE OF INTEREST FOR THE WEEK IS NORTHERN STREAM SHORTWAVE
ENERGY DIGGING THROUGH THE GREAT LAKES THU AND TO THE MID ATLANTIC/SE
US COAST BY FRIDAY...WITH POTENTIAL CLOSED LOW DEVELOPMENT OVER THE
NE/NEW ENGLAND. AS MENTIONED ABOVE SOME DIFFERENCES EXIST IN DEGREE
AND RATE OF AMPLIFICATION...WITH SENSITIVITY LYING IN STRENGTH OF
UPPER ENERGY ENTERING WESTERN CANADA TUE MORNING AND DEGREE OF
PHASING WITH DETERIORATING SW TROUGHING AS IT DIGS SE. THIS MANIFESTS
IN DIFFERENCES IN EXACT TIMING AND LOCATION OF CYCLOGENESIS ALONG
THE COAST/COASTAL PLAIN AND TRACK OF THIS SECONDARY LOW. HAVE
CONTINUED WITH MIDDLE OF THE ROAD SOLUTION...WITH DEVELOPMENT OF A
SECONDARY LOW ACROSS MID ATLANTIC THU AND THEN TRACKING NORTH ACROSS
THE REGION THU NIGHT.

WITH GOOD SYNOPTIC SUPPORT AND POTENTIAL FOR ENTRAINING OF MOISTURE
FROM EASTERN PACIFIC TROPICAL CYCLONE VANCE...WILL CONTINUE WITH
LIKELY POPS FOR THU INTO THU NIGHT. A POTENTIAL EXISTS FOR A
PERIOD OF HEAVY RAIN DURING THIS TIME IF MORE AMPLIFIED SOLUTIONS
VERIFY. MODELS IN DECENT AGREEMENT WITH THE INTENSIFYING LOW
PRESSURE SYSTEM DEPARTING N THROUGH SE CANADA ON FRIDAY AS THE
TROUGH AXIS NEGATIVELY PIVOTS THROUGH THE REGION. THIS SHOULD
ALLOW FOR GRADUAL DRYING CONDS WITH CAA ON MODERATE NW WINDS THRU
FRI NIGHT...GRADUALLY RELENTING ON SAT.

ANOTHER SHORTWAVE APPROACHES FOR SUNDAY WITH POTENTIAL FOR ANOTHER
ROUND OF UNSETTLED WEATHER.

Okay, sroc I am going to be nice here but I do not understand JB recent post DGEX model? What the heck is that?  I found it and it shows a major bomb at 108 hrs, bringing screaming winds and rain to the area, but this is def off from the 6th, two days is quite a difference. Or is this a different system? Below is the image, is this a reliable model or used at all?  And why is he posting it, eems like another fantasys storm, but Euro showed it now this?

That's this week's system but it phased over northern NE. That model is the worst. Can be ignored.

Ok thanks Frank. Didn't make much sense to me.

today nam and gfs have backed off of the heavy rain for thurs. now showing about 1/2 inch.

It certainly did Al, but I think it has a lot to do with how fast the moisture from x-vance makes it across US.

Unfort I don't have time to post much on this. What I will say is don't be fooled by the American models under estimating potential rainfall. There is a tropical moisture feed associated with the front streaming in from SE PAC. Here is a nice satellite loop showing it.
http://www.goes.noaa.gov/dml/comp/goes/nhem/rb.html



As soon as the arctic disturbance, that is currently located over Minnesota on this loop, catches up to the front a LP will develop along the front.  It will probably lift up past us somewhere over Eastern Pa, or NW NJ.  When it does so a triple point might form, cold front, warm front and occluded front, all meet at one point (center of LP) and enhanced lift occurs.  With a tropical moisture feed heavier totals ie: 2-3" could occur in and around the areas where the LP center passes.  
http://www.goes.noaa.gov/dml/comp/goes/nhem/wv.html



Right now a general 0.5"-1.5" should occur with higher totals between Queens NY and NW NJ/E Pa.

NWS feels this will be a last minute decision too.

MODELS ARE IN GOOD AGREEMENT WITH THE H5 PATTERN INTO FRI.
DEVIATIONS THEN COME INTO PLAY DUE TO THE PHASING OF THE NORTHERN
AND SOUTHERN STREAM BRANCHES OF THE JET RESULTING IN A DEEP
NEGATIVELY TILTED TROUGH ACROSS THE EASTERN CONUS. THIS LEADS TO
TIMING AND AMPLITUDE DIFFERENCES IN THE UPPER FLOW AND ALSO RESULTS
IN UNCERTAINTY IN THE CONSOLIDATION AND TRACK OF THE SFC LOW.

WHAT SEEMS FAIRLY CERTAIN IS THAT ANOTHER STORM SYSTEM WILL IMPACT
THE AREA THU INTO FRI PRODUCING A FEW INCHES OF RAIN AND WINDY
CONDITIONS...IN ADDITION TO THE POTENTIAL FOR MINOR COASTAL
IMPACT. DUE TO THE SPREAD IN THE TRACK OF THE LOW...THE DETAILS
REMAIN FUZZY AND MAY TAKE A FEW MORE MODEL RUNS TO BE RESOLVED AND
FOR CONFIDENCE TO INCREASE.

AS THE STORM LIFTS THROUGH NEW ENGLAND AND INTO THE CANADIAN
MARITIMES FRI/FRI NIGHT...IT WILL INTENSIFY WITH A TIGHT PRES
GRADIENT REMAINING ACROSS THE AREA WITH HIGH PRES BUILDING OVER THE
SOUTHEAST.

When might we have a clearer idea about Thursday? My boyfriend & I have Broadway tickets for Thursday night and had taken the day off work to spend the day in the city prior to the show. I'm assuming that's probably not happening not since it is supposed to be so rainy, but I want to know what I'm getting myself into for late afternoon - nighttime (say from 3 or 4 until 11), when we will be in for dinner and the show.

sabamfa wrote:When might we have a clearer idea about Thursday? My boyfriend & I have Broadway tickets for Thursday night and had taken the day off work to spend the day in the city prior to the show. I'm assuming that's probably not happening not since it is supposed to be so rainy, but I want to know what I'm getting myself into for late afternoon - nighttime (say from 3 or 4 until 11), when we will be in for dinner and the show.

Latest guidance is actually trending weaker and weaker with this storm. The 12z EURO and 18z GFS do not even show a quarter of an inch of rainfall for our area on Thursday. Just a period of light showers. I think your night should be ok. If I had to choose a time period of moderate rain to fall, it will be between 2-6pm. Check back in the morning. Tonights 00z runs will tell the full story

posted this in the other thread. from nws.....

.LONG TERM /THURSDAY THROUGH MONDAY/...

TWO POTENTIAL STORMS IN THE LONG TERM.

THE FIRST IS THU INTO FRI. THE TREND APPEARS TO BE E WITH THE MODEL
SOLNS. THE GFS ENSEMBLES AND OPERATIONAL GFS AND ECMWF ARE TIGHTLY
CLUSTERED. THIS BRINGS A TRACK OVER OR JUST E OF THE CWA. A TRACK
OVER THE CWA COULD DRY SLOT THE AREA...KEEPING PCPN TOTALS TO A
HALF INCH OR LESS. HOWEVER...ANY JOG TO THE W OR MORE LIKELY TO THE
E BRINGS THE POTENTIAL TO AROUND 1.5 INCHES. FOR THE MOST PART PCPN
ENDS FRI MRNG...HOWEVER THE ECMWF WHICH IS ON THE ERN EDGE OF THE
GUIDANCE DOES PRODUCE SOME MEASURABLE WRAPAROUND PCPN. IF THIS
VERIFIES...THERE COULD BE SOME FLAKES AT LEAST MIXED IN...ESPECIALLY
INTERIOR...AS THE COLD AIR IS DRAWN SWD. THIS IS STILL AN OUTLYING
SOLN...BUT BEARS WATCHING DUE TO THE TREND.

The 00z NAM and 00z GFS models tonight paint an even drier picture for the region on Thursday. Recent guidance is suggesting the southeast energy once pegged to be picked up by an arctic trough and bring a slug of moisture to the area, instead will remain confined in the southeast and miss the trough. As a result, we see little precipitation from the H5 energy embedded into the trough which transfers energy nearly right over NYC. The transfer puts the Philly / NYC Metro regions in a dry slot. Perhaps not even a quarter of an inch of rain will fall over the area.

00z GFS total qpf

sroc4 wrote:Unfort I don't have time to post much on this. What I will say is don't be fooled by the American models under estimating potential rainfall. There is a tropical moisture feed associated with the front streaming in from SE PAC. Here is a nice satellite loop showing.
http://www.goes.noaa.gov/dml/comp/goes/nhem/rb.html



As soon as the arctic disturbance, that is currently located over Minnesota on this loop, catches up to the front a LP will develop along the front.  It will probably lift up past us somewhere over Eastern Pa, or NW NJ.  When it does so a triple point might form, cold front, warm front and occluded front, all meet at one point (center of LP) and enhanced lift occurs.  With a tropical moisture feed heavier totals ie: 2-3" could occur in and around the areas where the LP center passes.  
http://www.goes.noaa.gov/dml/comp/goes/nhem/wv.html



Right now a general 0.5"-1.5" should occur with higher totals between Queens NY and NW NJ/E Pa.

Well it's hard to go against the models trending drier. I think it's because the front with the moisture feed pushes a tad to far to the east. I still think it's wetter than what last nights Runs are showing however. I'm sticking with my original idea but lowered my high end amts. that most of us will see 0.5-1". But I still believe that there will be an area of higher amts ie:1-2" between Queens and NW NJ in areas of enhanced lifting. That area may have to shift east however to include the rest of LI. IF higher amount occur it will probably be isolated and not include the entire area I stated above.  Here is my CYA. I really haven't had the time to spend a lot of time with this system so I may bust horribly.  

Todays nam and gfs have trended wetter. .5 to 1".

That makes more sense. Strongly feel most of us should receive half an inch

GFS shows winds on Friday to be quite gusty, generally 18-21mph sustained with gusts 30-40, is a guess on the gusts.  At least it won'e raining and struggling with a rmbrulla.  LI looks to get quite buffeted with more like 20-30mph sustained with higher gusts.  That is IF the models are right.

So the alarms have sounded here at Lyndon State. With the shift in the storm track to our east, cold air advection will be able to settle in while there is still precip left. The college is currently forecasting rain tmw evening, mixing and then eventually changing to snow late tomorrow night with accumulations of 2-4in here at the college (1,000ft) and just above us 4-6in above 2,000 ft.

Mets2695 wrote:So the alarms have sounded here at Lyndon State. With the shift in the storm track to our east, cold air advection will be able to settle in while there is still precip left. The college is currently forecasting rain tmw evening, mixing and then eventually changing to snow late tomorrow night with accumulations of 2-4in here at the college (1,000ft) and just above us 4-6in above 2,000 ft.

Yea that sounds about right. Take pics!

Mets2695 wrote:So the alarms have sounded here at Lyndon State. With the shift in the storm track to our east, cold air advection will be able to settle in while there is still precip left. The college is currently forecasting rain tmw evening, mixing and then eventually changing to snow late tomorrow night with accumulations of 2-4in here at the college (1,000ft) and just above us 4-6in above 2,000 ft.

Nice kid enjoy the 1st snowfall!

Well, the NAM came in really warm for me. Gives me a trace of snow and confines the accumulating snow to northern Maine. Could this just be the Nam's warm bias?

NAM is a worthless piece of crap. Iv'e been watching it this Fall and I seriously do not think I will look at it ever again.

EURO and GFS look solid for at least a 1-3 inch snowfall. I think you'll be fine.

Alright, Ill wait for the 0z GFS before i get concerned.

Current radar showing rain developing over DC-Philly and slowly moving north. Going to be a rather unsettled day tomorrow, but still think it comes to an end between 3-5pm

http://www.accuweather.com/en/us/new-york/nmigs-radar

GFS also moved heaviest precip out by the time the cold air comes in and gives me a trace to an inch at most.