Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Burlington Vermont
147 am EDT Friday Aug 1 2014
a typical Summer weather pattern will be the rule Friday and
continuing through the weekend and into early next week.
Temperatures will be near normal...however humidity levels will
slowly increase. This will lead to the development of showers and
thunderstorms...especially during the afternoon and early evening.
Near term /until 8 am this morning/...
as of 129 am EDT Friday...going forecast in real good shape with
just a few clouds...no precipitation...and fog developing during
the early morning. Grids have this covered well and only minor
tweaks needed...mainly to lower minimum temperatures just a
bit...especially over the northern Adirondacks.
Short term /8 am this morning through Saturday night/...
as of 345 PM EDT Thursday...short term models are in fair
agreement for the period. In general we will be under the
influence of southwest flow, meaning a slow increase in
temperatures and moisture.
Friday: no dynamic forcing mechanisms (i.E. Short waves or
fronts), so terrain will be the driving influence. Combined with
daytime heating, we should see clouds develop over the higher
terrain and perhaps an isolated shower or T-storm. 850mb
temperatures warm to 12-13c, so this will support highs around 80f
in the valleys -- very close to normal. Anything that does form
will be just "garden variety" in strength and should fade away
just prior to sunset. Friday night should be generally quiet.
Could be some patchy fog, though looks like some clouds will be
streaming up from the south and this could limit fog coverage. At
this point, left out any mention of fog.
Saturday: getting a little more interesting with regard to the
synoptic pattern. A trough will be forming along the middle-Atlantic
coast and start to focus clouds/precipitation down there. A skinny
weak surface ridge will be nearly on top of US, however with the
south/southwest flow aloft, some moisture will be advected in from
that coastal trough. What it means for sensible weather is that
there will be a higher chance/better coverage of afternoon showers
and storms. Took a model blend and have 40-60 probability of precipitation across the
region. Precipitable water values should be rising to 1.3" or a
little higher. Not totally out of the Ordinary, but a signal that
locally heavy downpours are quite possible. A little tricky on
the temperatures. Increased moisture and clouds may very well
offset things. 850mb temperatures still up around 12-13c, so with
full sun we are looking at upper 70s- lower 80s, however with some
guidance suggesting cooler conditions due to the clouds, I have
trended a bit cooler than what I have for Friday.
Saturday night: looks like some additional moisture pushes north
from that coastal trough. Guidance suggests some light
precipitation possible all night. Still think the diurnal signal
will hold strong, so not a lot of shower activity is expected, but
clouds will certainly be around. This will hold temperatures a bit
warmer -- upper 50s to lower 60s. Dew points will also be creeping
up, so a bit of a muggy night.
Long term /Sunday through Thursday/...
as of 345 PM EDT Thursday...upper level wave/trough will move
across the region Sunday...producing showers and thunderstorms in
the diurnal heating of the day. Models bring precipitable waters near 1.5
inches...in moistening SW flow. Sunday will have the best chance
for heavy showers and thunderstorms for the extended period.
The unsettled weather pattern will continue through the middle of
the week as several upper level impulses move across the region
along the zonal flow. The air will not be as moist and less
instability is expected...so have only included slight chance for
thunderstorms at the moment.
Temperatures will be fairly uniform with maxes reaching the m60s in
the mountains to u70s/l80s in the valleys. Min temperatures will range from the
m50s in the mountains to l60s in the valleys. But a slight cooling
trend will be seen mid-week.
Aviation /06z Friday through Tuesday/...
through 06z Saturday...primarily VFR conditions are expected
through the period with clear skies for the overnight hours...and
diurnal cumulus developing after 15z Friday. Only exception will
be overnight fog at kslk/kmpv and possibly kpbg...most dense at
kslk and kmpv down to vlifr 06-08z through 11-13z.
Outlook 06z Saturday through Tuesday...
mainly VFR although brief periods of MVFR possible in scattered
showers or thunderstorm each day which will be most likely during