Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Burlington Vermont
142 am EDT Sat Oct 10 2015
a cold front will move through the region early tonight with rain
showers coming to an end late this evening. A ridge of high
pressure will build east from the Great Lakes on Saturday and will
remain over the north country through Columbus day. Temperatures
will warm into the 60s on Sunday and into the 70s on Columbus day.
The next chance for rain showers across the north country will be
on Tuesday ahead of a cold front.
Near term /until 7 am this morning/...
as of 1036 PM EDT Friday...surface cold front at 02z has recently
pushed south of all Vermont zones and lingering/isolated rain showers
are generally coming to an end across central and S-central Vermont. Infrared
imagery also indicates some clearing moving into the St. Lawrence
Valley. Could see a lingering sprinkle or two...but generally dry
for the balance of the overnight period.
Winds behind the cold frontal boundary are moderately strong from
the N-NW...and will continue through the first half of tonight before
gradually diminishing. Still sustained at 13kts at btv as of
0230z. Low overcast will linger in most sections (except the St.
Lawrence valley)...with slow clearing 07-11z (from NW-se).
Moderately strong cold advection will result in lows in the middle-
upper 30s across most sections of the north country. Frost and fog
potl will be mitigated by clouds and breezy conditions overnight.
For the higher Summit levels...looking for lows in the upper 20s. No
cloud ice expected with shallow stratus layer after midnight...but
could see a bit of riming across the higher summits during the
Short term /7 am this morning through Sunday night/...
as of 357 PM EDT Friday...a ridge of high pressure will build
east from the Great Lakes on Saturday with mostly sunny skies
expected. Highs will be mainly in the 50s on Saturday...except in
the 40s over the higher elevations. High pressure will move off
the New England coast Saturday night which will allow for
southerly winds to develop across the region with min temperatures
Saturday night not as cool as tonight. Temperatures will warm into
the 60s on Sunday under partly sunny skies. Models showing
moisture associated with a warm front across Quebec will stay in
Canada and thus expecting a dry forecast on Sunday...with just
some clouds associated with this warm front across the region on
Sunday. Expecting skies to clear out Sunday night...but southerly
winds will help to keep temperatures up Sunday night.
Long term /Monday through Friday/...
as of 315 PM EDT Friday...forecast remains on track with warmest
day expected on Monday and best chance of widespread light rain
showers on Tuesday. Large scale pattern will feature weak short
wave ridge for early this upcoming week...but a deepening
middle/upper level trough is expected by midweek into next weekend.
This will support above normal temperatures for Monday into Tuesday...near
normal Wednesday...and below normal for Thursday into next weekend.
The first in a series of short waves and surface boundaries will
impact our forecast area on Tuesday. Both GFS/European model (ecmwf) show good
narrow ribbon of 850 to 500mb moisture along with some enhanced
lift from digging short wave energy and trough development. Have
increased probability of precipitation to low likely in the mountains and high chance in
the valleys. Given the narrow axis of moisture and southwest low
level wind profiles...expecting some quantitative precipitation forecast shadowing in the
Champlain Valley. Rainfall amounts look to range between 0.10 and
0.40 at this time...with greatest values in the mountains.
Additional spokes of energy and several weak secondary cold front
will rotate around developing middle/upper level trough across the
northeast Continental U.S. Wednesday through Friday. Will mention low chance probability of precipitation
with greatest potential for quantitative precipitation forecast in the mountains. As cooler air
moves across the warmer Great Lakes waters...some additional lake
enhanced moisture is possible into the western dacks.
Behind each trough passage column continues to cool with thermal
profiles by the end of the week cold enough to support some wet
snow flakes in the higher summits above 2500 feet...especially as 925mb
temperatures approach 0c by next Friday. Prognosticated 850mb temperatures near 12c on
Monday support upper 60s to middle 70s. On Tuesday and Wednesday
850mb temperatures fall back between -1c and +2c supporting highs in the
40s mountains to middle/upper 50s warmer valleys. Summits above 3500
feet will stay mainly in the 30s to lower 40s. Even cooler temperatures
arrives by Friday into Saturday with highs mainly in the upper 30s
to middle 40s mountains towns to Lower/Middle 50s warmer valleys.
Aviation /06z Saturday through Wednesday/...
through 06z Sunday...sct/bkn mainly VFR ceilings to generally trend
sky clear/scattered at all terminals by later this morning. Some lingering
MVFR possible through 12z at kslk/kmpv. No precipitation expected.
Winds light west to northwesterly from 5 to 10 knots through 18z,
then trending south to southwesterly around 5 knots thereafter.
Outlook 06z Sunday through Tuesday... surface high pressure with
VFR conditions prevail on Saturday into early next week. IFR/LIFR
are possible in fog/br development at mpv/slk...especially Sunday
morning. Breezy southwest winds develop late Sunday into
Monday...before next boundary with light showers arrives on