Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KBTV 300735
Area Forecast Discussion
National Weather Service Burlington VT
335 AM EDT MON MAY 30 2016
Scattered showers and thunderstorms will continue through this
evening as an upper level shortwave tracks through the North
Country. Locally heavy downpours remain possible. Expect
additional showers again on Memorial Day with slightly cooler
high temperatures. Dry conditions are expected Tuesday through
Thursday with high temperatures generally in the mid to upper 70s
and lower humidity levels.
.NEAR TERM /THROUGH TONIGHT/...
As of 117 AM EDT Monday...Moist plume (precipitable water values
of 1.5" to 1.6") will remain over the North Country overnight in
advance of sfc cold front moving ewd across Southeastern Ontario
and Lake Erie at 02Z. Instability has waned across the region, a
combination of loss of daytime heating and broad region of shower
and thunderstorm activity that has affected the region this
afternoon and evening, and associated rain cooled low-level air
now in place. We did see a few areas of damaging winds earlier
today around St. Albans/Sheldon VT and also Essex County NY near
Lake Champlain with separate thunderstorms. Also, radar estimated
rainfall in excess of 4" indicated along the nrn slopes of the
Adirondacks (central Franklin County NY) with training
thunderstorm activity mid-late aftn. This occurred largely in a
wilderness area, with no reports of flooding thus far. Please
refer to our local storm reports for specific details on storm
damage and any future flooding reports that we may acquire.
500mb ridge continues to break down overnight in response to
shortwave trough crossing the Eastern Great Lakes. Moderately
high PW values, mid-level height falls, and increasingly cyclonic
flow will maintain chances for shower activity overnight, though
overall coverage of rainfall should decrease. An additional
0.2-0.3" rainfall is possible through the remainder of the
overnight period. Will see low temperatures mainly in the low to
mid 60s, with cooler temps across Eastern VT with some marine
modified air working into Eastern VT on light E-SE flow (lows in
the Upper 50s in this region). Given today`s rainfall, will see
patchy fog overnight, especially in the valleys within the nrn
Adirondack region where rainfall was locally heaviest.
For Memorial Day, anticipate another day of scattered showers
with a few embedded thunderstorms. It won`t be quite as warm as
today so instability will be limited however through will be
enough unstable air to see a few isolated thunderstorms. Best
threat central into s-central VT. Expected max temps tomorrow will
be in the low to mid 80s as the upper level trough finally starts
to push through the North Country.
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
-- Changed Discussion --As of 335 AM EDT Monday...Quiet, seasonably mild weather is then
expected for the Tuesday through Thursday time frame with surface
high pressure being the dominant weather feature. Other than a
passing sprinkle or light shower across the northern Green
Mountains on Tuesday with a passing upper shortwave trough, dry
weather is expected through the period. Daily high temperatures
will range from the mid 70s to lower 80s with overnight lows
generally in the 45 to 55 range with some variability.
-- End Changed Discussion --
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
-- Changed Discussion --As of 335 AM EDT Monday...By later in the week there is
increasing confidence that we`ll return to an on and off showery
regime as a series of shortwave troughs/fronts push into the
region. There is broad agreement among this morning`s models that
a weakening frontal zone will limp into the region by Thursday
night into Friday before washing out is it presses east by next
Saturday. Given the current consensus will maintain forecast
continuity offering chance pops for showers during this period
with little airmass change expected.
Thereafter confidence lowers in regard to potential development of a
larger-scale longwave trough or closed upper system to our northwest
and its eventual eastward movement/potential impacts.
Teleconnections and latest ensemble output does suggest
amplification of western conus ridging which would tend to foster
lowering heights/troughing from the upper Midwest/Great Lakes
eastward from Sunday onward into next week. However, deterministic
output remains at odds on how deep this feature will be, the degree
to which it digs south and east over time and what interaction, if
any it has with deeper moisture across the mid-Atlantic/southeast.
Given at least the broader consensus in this overall troughing
scenario will bring solid chance pops for showers and possibly a few
storms by later Sunday onward into next Monday. Temperatures should
remain within a few degrees of seasonable levels with daily highs in
the 70s and overnight lows mainly in the 45 to 55 range.
-- End Changed Discussion --
.AVIATION /08Z Monday THROUGH Friday/...
Through 06z Tuesday...concerned with areas of BR possible with
locally dense fog at SLK due to today`s rainfall. May see 4-6sm
BR at the remaining TAF locations during the pre-dawn period.
Generally VFR for the daylight hours on today. May see some
additional showers/isolated thunderstorms with peak afternoon
heating...with best chance of thunderstorms development across
central and s-central VT. Surface winds becoming generally S-SW
10-15kts late morning through the afternoon hours on Monday.
Outlook 06z Tuesday through Friday...Primarily VFR TUE-THU with
just a chance of late night fog each night at SLK/MPV mainly
07-11Z. Next frontal system and attendant upper level trough
approaching from the Great Lakes region will bring a chance for
showers Thursday night into Friday with brief intervals of MVFR to
IFR possible associated with rainfall.