Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Burlington Vermont
128 am EDT Tuesday may 5 2015
a weak surface cold front will produce scattered showers
overnight and cooler temperatures on Tuesday across the north
country. Rainfall amounts will be light and generally under a
tenth of an inch. Surface high pressure will redevelop across the
region with dry conditions and above normal temperatures
continuing through Friday.
Near term /until 6 am this morning/...
as of 110 am EDT Tuesday...composite radar loop showing rain
showers moving out of the region faster than the previous
forecast. Thus...have lowered probability of precipitation for the remainder of the
Short term /6 am this morning through Wednesday night/...
as of 340 PM EDT Monday...surface boundary will be located across
southern New England by 12z Tuesday...as northwest winds and drier
air develops quickly across our region. Sounding profiles show a
weaker wind field and less mixing than Monday across our region on
Tuesday. Thinking a few gusts in the favorable northwest downslope
regions of the lower CT River Valley and near mpv will reach in
the 20 to 25 miles per hour range. Elsewhere...expect winds in the 5 to 10
miles per hour range with gusts 15 to 20 miles per hour. Soundings once again support
drier air around 850mb where the dewpoints fall below 0c mixing to the
surface...especially during the afternoon hours. This will result in
surface relative humidity values falling into the 23% to 33% range....with mostly
sunny skies. A few shallow fair weather cumulus clouds may develop
over the mountains prognosticated 850 mb temperatures drop 3 to 5 degrees from
Monday...supporting highs in the 60s mountain towns to l70s in the
warmer urban areas of the Champlain Valley.
Tuesday night through Wednesday night...very dry conditions will
continue but with surface high pressure building directly overhead...winds
will be mainly terrain driven at 5 to 15 miles per hour daily. Expecting a
chilly night on Tuesday night with 1028 mb surface high pressure located
across western New York...resulting in light winds and clear skies. These
conditions will allow temperatures to fall very quickly after sunset with
lows by Wednesday morning ranging from the lower 20s in the protected
mountain valleys to M/u 30s Champlain and Saint Lawrence valleys. Some
patchy frost will be possible...where the growing season has been
declared started in the Champlain and Saint Lawrence valleys. On
Wednesday expect plenty of sunshine and warm temperatures with surface high
pressure overhead. Prognosticated 850 mb temperatures range from 6 to 8c...with dry air
mass support highs in the M/u 60s mountain towns to l/M 70s warmer
valleys. Will trend cooler than guidance at night and warmer
during the day...given the lack of moisture and very dry surface
Long term /Thursday through Monday/...
as of 323 PM EDT Monday...mainly dry and pleasant Spring weather
Thursday into Friday followed by increasing chances for showers
next weekend. Temperatures will be above normal through the
A ridge of high pressure will prevail across the region into
Friday. Fair and mainly dry weather expected...with just the
chance for a few widely scattered showers Friday...but no more
than slight chance probability of precipitation indicated.
A weak cold front will move south from Canada Saturday and then
become stationary somewhere across the northeast Sunday into
Monday. Upper level support lacking however...as 500 mb ridge
remains over the region. Expect considerable clouds and the chance
of showers each day. Also the slight chance of thunderstorms
Maximum temperatures will average well above normal through the period. High
temperatures Thursday through Saturday will be in the middle 70s to lower
80s...then a bit cooler Sunday and Monday due more cloud cover and
higher chances for showers.
Aviation /06z Tuesday through Saturday/...
through 06z Wednesday...mainly VFR conditions through the period.
Some lingering MVFR ceilings following departure of cold
front...but this should be fairly short lived and have covered it
with tempo groups. Drier air builds in Tuesday morning with just
scattered clouds expected most locations after 12z. Winds will
also become light.
Outlook 06z Wednesday through Sunday...
06z Wednesday-00z Saturday...VFR conditions with weak surface
high pressure prevailing for much of the period.
00z Saturday-00z Monday...mainly VFR with areas of MVFR/IFR in
scattered showers and thunderstorms.
more drying is expected Tuesday afternoon and continuing right
through the end of the week. Gusty northwest winds will exist
Tuesday afternoon over eastern Vermont as afternoon humidities
lower into the 20 percent range. Thus...fire weather concerns will
exist Tuesday afternoon over the entire area as 1 and 10 hour
fuels are critically low. Not much in the way of wind is expected
Wednesday through Friday...but plenty of sun...no
precipitation...and further drying of the 1 and 10 hour fuels will
keep fire weather concerns going for the middle to latter part of
as of 110 am EDT Tuesday...boaters should also keep in mind that
water temperatures remain cold - in the 40s. Swimming early in the
season is discouraged as immersion for prolonged periods of time
could produce hypothermia given these water temperatures.