647 
fxus61 kaly 070533 
afdaly 


Area forecast discussion 
National Weather Service Albany New York 
130 am EDT Tuesday Oct 7 2008 


Synopsis... 
an area of Canadian high pressure will move across the northeast 
through Wednesday. This will allow for chilly mornings and 
increasingly warmer afternoons across the region for Tuesday and 
Wednesday. A frontal boundary will approach the area on 
Thursday...bringing the chance for a few showers. 


&& 


Near term /until 8 am Tuesday morning/... 
upper level trough is now well east of the region across the Gulf 
of Maine...allowing for ridging across the Great Lakes to shift 
towards our region. Latest satellite picture shows clear skies County Warning Area 
wide and plenty of dry air at middle levels according to h20 loop as well. 
This has allowed temperatures to rapidly fall in most areas this 
evening. Boundary layer is just a bit more moist than models have 
projected...which could allow for some patchy fog to briefly 
develop overnight at usual suspect places. However...00z aly 
sounding shows a high inversion height /around 800 mb/ with about 
20 kts of wind from just above the deck up to the inversion level. 
Would think that this could help mix air somewhat enough to 
prevent any widespread fog from developing tonight. With weak cold air advection 
currently ongoing...wouldn/T be surprised if dew points continued to drop 
through the first half of the night as well. At this point...will 
leave forecasted mins alone and only do a minor update to account 
for current trends. Accordingly...will continue current 
freeze/frost headlines as is...seeing no need to mess with them at 
this time. 


&& 


Short term /8 am Tuesday morning through Thursday/... 
not so sure how cold it will get Tuesday night. Mav guidance by far 
the coldest and believe that is overdone. Warming will be occurring 
aloft with 850 mb temperatures expected to warm to 8 to 10 degrees 
celsius by 12z/Wednesday. Plus some high level clouds may reach the 
region. Surface high will move off region and winds will be light 
and variable. Where growing season does not end tonight will need 
freeze warnings and/or frost advisories for Tuesday night. 


The surface high will slide off to our south and east Wednesday and 
the upper ridge axis will shift to the east. Temperatures will begin 
to moderate. After a cold start temperatures will rebound to above 
normal levels. Higher level clouds will move in ahead of a frontal 
boundary which is expected to cross the region Thursday. Model 
solutions really begin to diverge by Thursday. Expect another mild 
day with above normal temperatures Thursday along with a chance for 
showers. 


&& 


Long term /Thursday night through Monday/... 
around the start of the extended period...a frontal system in the 
northern stream will be pushing through the northeast. Have tapered 
off probability of precipitation through the night as the best forcing will be moving east 
of the region. Min temperatures will be held several degrees above seasonal 
normals as the associated cloud cover and shower activity will help 
keep temperatures from dropping too much. 


The weekend period is not being handled too well by the models at 
this point. Both the European model (ecmwf) and GFS have been holding steady on their 
various patterns for several runs now. The GFS is determined to 
bring a cutoff northeastward from the southeast Friday and up the 
Atlantic coast for the weekend. This would bring an area of showers 
to the region for sometime Friday night into Saturday night. 
Meanwhile...the European model (ecmwf) has continued to show strong high pressure at 
the surface developing across the Great Lakes on Friday...which 
would spread eastward over the weekend...keeping the cutoff 
suppressed across the southeast. Will tend to favor the European model (ecmwf) 
solution...which has support from both the 12z UKMET and 12z ggem. 
Still...to account for the uncertainty and to preserve some 
continuity with previous forecasts...will still hold low chance probability of precipitation 
for a brief period for southern and eastern areas of the County Warning Area over 
the weekend. Will keep temperatures a few degrees above normal...as strong 
ridging depicted by European model (ecmwf) would allow for temperatures to average warmer 
than seasonal normals. 


&& 


Aviation /05z Tuesday through Saturday/... 
a rather complicated situation regarding visibility during the 
predawn hours. Currently temperatures are within one degree of 
the dewpoint at several sites including kgfl...kpou...kaqw...kddh 
kdxr...and kmgj. Of these so far only kaqw had significant fog... 
they were down to 1/4 mile. Kgfl was down to IFR for about an hour 
before some light winds stirred up the air sending the temperature 
up seven degrees. Winds across the forecast area have become calm 
aside from a 3 knot northeasterly wind at krme...and skies are 
clear. We have included a tempo to IFR except at kalb where the 
field elevation is likely to help keep the worst of the fog to 
the north and down by the river. Whatever fog and low stratus 
does form prior to daybreak will mix out between 1200 and 1400 gmt 
..after which flight conditions should be VFR for the rest of the 
day. Winds will be calm prior to daybreak and then 5 to 10 knots 
from the north during the day today...diminishing to less than 5 
knots late this evening. Some high clouds are likely to come in 
from the west late tonight in advance of a frontal system moving 
east out of nation/S midsection. 


Outlook... 
tonight-Wed...VFR...no sig weather. 
Thu-Sat...VFR/MVFR...chc showers. 


&& 


Fire weather... 
cool Canadian high pressure will build southward into the region and 
will dominate our weather through middle week. Temperatures will begin 
to moderate during the day Wednesday as the high shifts off to our 
southeast and a southerly flow of warmer air develops. 


The relative humidity will recover to 90 to near 100 percent 
tonight and drop to minimums of 30 to 40 Tuesday afternoon. Light 
northwesterly winds tonight increasing to 5 to 10 miles per hour Tuesday 
then diminishing in the evening. 


&& 


Hydrology... 
river flows will continue low as rainfall yesterday was very light 
and will have little effect on the rivers. Our next chance for rain 
will come late in the week when a frontal boundary is expected to 
move across the region. This rain is expected to amount to less 
than half an inch and will have little...if any...effect on the 
rivers. 


For details on the rivers...please visit the advanced hydrologic 
prediction service /ahps/ graphs on our website. 


&& 


Aly watches/warnings/advisories... 
CT...frost advisory until 9 am EDT Tuesday for ctz001-013. 
New York...freeze warning until 9 am EDT Tuesday for nyz038>043-047-048- 
051-054-061-063-066-083-084. 
Frost advisory until 9 am EDT Tuesday for nyz049-050-052-053- 
059-060-064-065. 
Massachusetts...freeze warning until 9 am EDT Tuesday for maz025. 
Vermont...freeze warning until 9 am EDT Tuesday for vtz014-015. 


&& 


$$ 
Synopsis...frugis 
near term...frugis 
short term...iaa 
long term...frugis 
aviation...rck 
fire weather...iaa 
hydrology...rck 

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