Weather

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Area forecast discussion 
National Weather Service Taunton Massachusetts 
535 PM EDT Sat Oct 11 2008 


Synopsis... 
high pressure will remain over the region bringing dry and pleasant 
weather with near normal temperatures into early next week. A cold 
front will move through New England Wednesday and bring a chance of 
showers. 


&& 


Near term /until 6 am Sunday morning/... 
pleasant dry weather continues tonight with deep layer ridge just to 
the west of New England. Temperatures will drop fairly quickly with 
sunset given dry dew points...light winds and clear skies. This will 
result in a chilly night outside of the urban areas. 


Short wave trough moves across New Brunswick and Nova Scotia late 
tonight. Little if any moisture associated with this feature...so 
not expecting any sensible weather. 


&& 


Short term /6 am Sunday morning through Sunday night/... 
the large scale flow this period will feature a stationary large 
amplitude ridge with its axis centered across the Ohio Valley 
northward into Canada. This flow around this ridge brings multiple 
short waves from Hudson Bay southeast into New Brunswick and Nova 
Scotia. 


The first short wave trough which is currently across central Quebec 
tracks southeast across New Brunswick and Nova Scotia overnight. The 
only sensible weather with this feature will be a subtle backdoor 
front...which has been well advertised by previous shifts. The front 
doesn/T show up well in the pressure field...but is noticeable in the 
low level thermal fields. So expect slightly cooler temperatures Sunday 
especially across eastern Massachusetts. 


Otherwise...expect another day of spectacular Fall weather with dry 
conditions and seasonable temperatures. 


The next short wave trough and associated backdoor front moves across 
the Canadian Maritimes late Sunday night. This feature has more 
moisture than its predecessor late tonight...but model xsections 
suggest moisture is confined to the middle and upper levels with dry 
air below. Therefore thinking main impacts will only be increased 
cloud cover late Sun night with any precipitation limited to a brief shower 
or sprinkle across eastern Massachusetts and southeast New Hampshire. 


&& 


Long term /Monday through Saturday/... 
medium range models are in fairly good agreement early in the long 
term period...then timing issues come into play as the upper level 
pattern becomes less amplified. Questions at this point will be 
timing through weak fronts and whether they continue to weaken as 
they pass across the region. 


Monday...weak backdoor cold front works down the coast during the 
morning. Expecting little if any precipitation with this front...mainly a 
wind shift line. Weak high pressure bubble works down out of Nova Scotia 
and across the waters. Cooler temperatures expected along the coast with an 
onshore flow...but will be warmer inland as winds remain from the 
N-NW. 


Monday night-Tuesday...highs merge as they slip down the New England 
coast...so expect winds to shift to east-southeast Monday night. Model cross 
sections indicating a low level marine inversion setting up. 
This...along with the onshore flow...could bring in low clouds and 
fog off the ocean along the South Coast...Cape Cod and the islands. 
Have added more clouds and patchy fog there. With lower sun 
angle...will take a couple of hours after sunrise for fog and clouds 
to burn off. Tuesday looks to be a beautiful day with highs in the 
Lower-Middle 70s. 


Wednesday-Thursday...as long wave ridge flattens over the northern 
tier states...upper flow becomes faster. Will see a couple of weak 
fronts in this fast flow. First...a weak front moves through 
Wednesday morning. Have mentioned slight chance probability of precipitation for Tuesday 
night and Wednesday...but not a lot of moisture or lift with this 
system with the dry west-northwest upper flow. This front washes out S of the 
region...then another front with an associated low works out of the 
Great Lakes. The low will lift NE into southern Quebec as the front 
slides through during Thursday. This seems to have a bit more energy 
associated with it but again...not a lot of deep moisture. So... 
have continued with slight chance probability of precipitation. Not a lot of confidence with 
this system however due to timing issues. 


Friday-Saturday...appears large high pressure will work out of the 
Midwest. However...as a broad long wave upper trough sets up over 
the eastern u... do have a wide spread as to a possible 
system moving up the coast for next Saturday...a week away. Did 
mention slight chance probability of precipitation for now...but low confidence. 


&& 


Aviation /21z Saturday through Thursday/... 
tonight...VFR. 


Sunday...VFR. 


Sun night...VFR with any ceilings 8-12 kft. 


Outlook...Monday through Thursday... 


Mainly VFR conditions. May see MVFR-IFR ceilings/visibilities Monday night and 
early Tuesday morning along the South Coast with low clouds and fog 
off the ocean. 


&& 


Marine... 
pleasant boating weather this period. Weak back door front moves 
across eastern New England waters late tonight and early Sunday. 
Light winds will become north-northeast 10-15 knots with a few gusts to 20 knots 
early. Winds diminish Sun afternoon as high builds over the New England. 


Sunday night...another backdoor front drops southward into the Gulf 
of ME and the ME coastal waters. Winds become west-southwest ahead of the front 
Sun night with possible a shift to north-northwest toward sunrise Cape Ann to 
the Merrimack. 


Outlook...Monday through Thursday... 


Monday...a backdoor cold front will work across the waters in the 
morning...with winds shifting to NE with a brief gust to 20 knots. 


Monday night-Tuesday night...high pressure builds down the coast. Winds 
shift back to S-SW. 


Wednesday-Wednesday night...another front works across the 
waters...then stalls and weakens. Winds briefly north-NE but less than 
15 knots..then shift back to S at night. 


Thursday...SW winds will pick up ahead of next front. May see gusts 
approach small craft criteria. Seas may build to near 5 feet. 


&& 


Box watches/warnings/advisories... 
CT...none. 
Massachusetts...none. 
New Hampshire...none. 
Rhode Island...none. 
Marine...none. 


&& 


$$ 
Synopsis...nocera/evt 
near term...nocera 
short term...nocera 
long term...evt 
aviation...nocera/evt 
marine...nocera/evt 

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