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fxus61 kbox 030147 
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Area forecast discussion 
National Weather Service Taunton Massachusetts 
848 PM EST Tuesday Dec 2 2008 


Synopsis... 
weak high pressure will provide dry and tranquil weather through 
Wednesday night. A cold front may bring a few light showers or 
sprinkles Thursday. Much colder air will follow in it/S wake. A low 
pressure system is expected to pass southeast of southern New England 
late in the weekend and may graze the region with some snow showers. 


&& 


Near term /until 6 am Wednesday morning/... 
previous forecast pretty much on track. The only change was to drop 
overnight lows across the interior a few degrees...where skies were 
mostly clear and winds were light. Across the coastal plain a fair 
amount of middle and high level clouds covered the region this 
evening. This in response to a moisture starve shortwave moving 
through the region. These middle/high clouds should gradually push off 
to the east overnight. 


Lows should range from around 20 across southwest New Hampshire/northwest 
Massachusetts...to the middle 30s in the urban heat island of Boston. Across the 
rest of the region...lows should mainly be in the 20s. 


&& 


Short term /6 am Wednesday morning through Wednesday night/... 
high pressure ridging dominates on Wednesday allowing for mostly 
sunny skies and relatively light winds. Stayed close to mavmos for 
maxes...which should yield highs around or slightly above normal. 


Upper trough and associated cold front will move across the Great 
Lakes Wednesday night. We should see an increasing southerly flow 
overnight on the coast and the higher terrain. Mostly clear skies are 
expected...but increasing cirrus is expected late. Remained pretty 
close to mavmos for mins. 


&& 


Long term /Thursday through Tuesday/... 
***no unusual winter weather on the horizon and delayed winter snow season 
continues*** 


General international model suite agreement through next Tuesday 
inclusive of 12z GFS/15z sref ensembles/12z op runs of the GFS/NAM/UKMET 
and European model (ecmwf). 


Departure from GFS MOS guide occurred next Tuesday when MOS guidance 
wind direction was 180 degrees out of phase with the 12z GFS and 
therefore defaulted to the 14z HPC wind guidance for next Tuesday. 


Forecast confidence for all parameters: generally at or above average through 
Tuesday morning then at or below average late next Tuesday. 


Snowfall per daily clms for orh/con as well looking at daily norms on 
nohrsc shows below normal 4 to 8 inches to date in New England. 


Climatology...the dailies while showing a few degrees above normal Thursday 
will be almost 10f below normal Sunday. 


The dailies... 


Thursday...mild ahead of a cold front passage that should generate scattered sprinkles or 
light showers interior. Gusty SW flow. Thursday night I trimmed previous 
4 am forecast guidance per 09z sref 3 hrly probability of precipitation for .01. The 18z op NAM 
continues trying to bring showers across southern New England... yet the UKMET European model (ecmwf) are 
dry. The 15z sref received after 20z today is offering a 30 pop Thursday 
evening vicinity cirrocumulus and the islands and this may be a weakness in the 
4pm kbox forecast. Hfc/short wave most effective southeast Canada. 


18z GFS says scattered sprinkles or light showers proceed across southeast third 
of southern New England Thursday evening. Again the Thursday evening part of the forecast for 
probability of precipitation is viewed with considerable uncertainty. 




Friday...cold and dry. Think temperatures will end up 2 or 3 degrees colder than 
the new kbox forecast during the daylight hours. Tried to cut GFS MOS 
guidance slightly. 


Saturday...tweener. Not much going on...though there could be some snow 
showers developing along the coast during the afternoon depending on 
bl wind direction and associated ocean effect development. Confidence 
on where and if any snow showers during the afternoon is below average. 


Sunday...looks to ME like a strengthening negative tilt short wave Burrows 
across Middle Atlantic States before lifting NE toward Georges Bank...generally 
too late for a major storm here. Instead...think there will be a 
cluster of MDT to heavy snow showers vicinity the vorticity maximum. Looks like a 
grazer...at worst and did little to change that thinking via our 
gridded probability of precipitation. I did change weather type from snow to snow showers...to be 
less ominous. Doesnt mean it can be a decent snow event for parts of 
the coast but at this time...no model is indicating that heavier scenario. 


Monday...instead...could see a decent amount of lake effect Monday 
morning during cold air advection north-northwest bl flow. Probability of precipitation and skycover raised for Outer 
Cape. 


Tuesday...appears to be dry high pressure...beginning of warm air advection at night. 
Little change to the previous 4am kbox forecast guidance. 


&& 


Aviation /02z Wednesday through Sunday/... 
tonight...VFR. 


Wednesday...VFR with light southwesterly flow. 


Wednesday night...VFR. 


Outlook...Thursday through Sunday... 


Thursday...VFR with scattered MVFR ceilings and visibilities in mainly afternoon 
-shra. Gusty SW winds 25-35 knots expected bos fmh hya and ack Thursday afternoon. 


Friday...VFR. 


Saturday...VFR may diminishing to MVFR in scattered late day snow or rain showers 
along the coast but this is not a high probability. 


Sunday...VFR except a period of MVFR or IFR conds in scattered snow showers 
coast...especially at night. Northwest wind gusts to 30 kts develop by night 
ack/bos. 


&& 


Marine... 


Overnight...winds well below Small Craft Advisory thresholds. However...seas remain 
up over much of our outer-waters and sounds this evening. Seas 
should continue to gradually diminish as high pressure builds in 
overnight...but they will remain high enough across our southeast 
outer-waters for Small Craft Advisory headlines. 


High pressure for Wednesday with relatively light winds. Seas on the outer 
waters still at or above 5 feet until late afternoon. 


Wednesday night...southerly flow begins to increase in advance of 
approaching cold front. Small craft winds/seas quite possible by 
late at night. 


Outlook...Thursday through Sunday... 


Winds and seas increase in advance of an upper level trough and cold 
front Thursday. Small Craft Advisory conditions expected...with a low 
to moderate probability of SW gale force gusts midday Thursday. No 
gale watch at this time and no Small Craft Advisory issued since we are still cleaning up the 
mainly hazardous seas advisory for the next 18 hours. 


Friday...Small Craft Advisory conditions continue...especially across 
the outer coastal waters...with winds and seas decreasing gradually. 


Saturday...expected to be quiet. 


Sunday...Small Craft Advisory likely at night with possible need for a gale at night. 


&& 


Box watches/warnings/advisories... 
CT...none. 
Massachusetts...none. 
New Hampshire...none. 
Rhode Island...none. 
Marine...Small Craft Advisory until midnight EST tonight for anz237-250. 
Small Craft Advisory until 5 PM EST Wednesday for anz254-255. 
Small Craft Advisory until 5 am EST Wednesday for anz235. 


&& 


$$ 
Synopsis...ekster 
near term...Frank 
short term...ekster 
long term...drag 
aviation...Frank/ekster/drag 
marine...Frank/ekster/drag 

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