National Weather Service Raw Text Product

645 
FXUS61 KBTV 020734
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
334 AM EDT Mon Jul 2 2018

.SYNOPSIS...
Historically significant heat wave continues today with near record
to record high temperatures in the mid to upper 90s. Oppressive 
humidity will continue today as well, with heat index values 
peaking between 100 and 110 degrees in most valley locations. A 
weak mid-level trough will shift eastward across northern New 
York this evening, bringing isolated to scattered thunderstorms 
to portions of northern New York and Vermont. A few strong 
storms are possible with brief heavy rainfall and localized 
strong wind gusts. Behind the trough, high temperatures will 
remain in the upper 80s to lower 90s for Tuesday and 
Independence Day, but humidity levels will be a bit more 
moderate. A cold front arriving Thursday night and Friday will 
bring widespread showers and thunderstorms, followed by long 
sought relief from the 90 plus degree temperatures on Friday and
Saturday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 230 AM EDT Monday...Rather incredible early morning 
underway with temperatures steady at 85F at BTV and a 73F 
dewpoint. The south wind around 10 mph feels like a misplaced 
trade wind from the tropics, a surreal VT wx experience. The 
south winds and scattered clouds in the Champlain Valley should 
hold early morning temps 80+, before soaring back to the mid- 
upr 90s areawide this afternoon. Today should be the hottest day
of this historic heat wave, with near record to record high 
temperatures expected once again. Dewpoints will remain near 
70F, resulting in continued oppressive humidity levels. With 
the forecast on track, no changes to ongoing Excessive Heat 
Warnings and Heat Advisories valid thru this evening. Winds will
increase from the south with PBL heating/mixing, reaching 10-15
mph this afternoon with a few gusts near 20 mph. 

It continues to appear that 700-500mb vorticity filament will 
shift ewd into the northern Adirondacks around 00Z Tuesday, 
along with weak sfc trough. Should be just enough forcing to 
initiate convective storms late aftn/early evening across nrn 
NY, with isolated scattered thunderstorms tracking ewd across 
the Champlain Valley and nrn VT 23-04Z time frame. With PW 
values near 2", included mention of heavy rainfall with any 
thunderstorm activity. May also see a damaging downburst or 
two...the SPC has portions of the forecast area in a marginal 
risk of severe t-storms for this possibility later today, per 
06Z Day 1 Outlook. Rain cooled outflow may well force 
temperatures into the mid 70s at BTV before midnight...we'll 
watch how that evolves for climate purposes (all-time record 
high-low is 78F at BTV, possible pending convective evolution).

Precip threat moves east and wanes overnight. May see some
patchy BR/FG late, especially in spots seeing tstm activity
earlier in the evening. Overnight lows generally in the low-mid
70s.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
As of 230 AM EDT Monday...Still looking for valley highs in the
lower 90s on Tuesday (4th consecutive day), but passage of the 
weak trough tonight will bring falling dewpoints into the low- 
mid 60s on Tuesday afternoon with light W-NW winds. Thus, 
humidity levels will be more moderate. Heat index values should 
peak near 95F in the Champlain and CT River Valleys (higher 
dewpoints hold on longest further east across ern VT). Looks 
marginal for extension of Heat Advisories into Tuesday, so will 
hold off on any extension at this time. 

Quiet conditions then expected for Tuesday night as deep 
ridging remains parked across the northeast. With the lower
dewpoints, should see lows Tuesday night mainly in the mid 60s
with PoPs NIL. July 4th will see valley highs in the low-mid
90s with partly to mostly sunny conditions. Best chance for an
isold shower or thunderstorm should be across s-central VT (20%
PoPs for Rutland/Windsor counties).

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 331 AM EDT Monday...The prolonged heat wave begins to 
come to an end at the start of the long term period as mid level
high continues to retrograde back to the west. Thursday will 
still see high temperatures in the upper 80s to lower 90s, but 
an upper level trough moving though the northern Great Lakes 
Region bring with it a frontal boundary Thursday evening and 
into Friday. Timing of the boundary keeps shifting by model run,
but with the abnormally hot air mass, widespread thunderstorms 
with the potential for some severe activity is very much in play
Thursday night through Friday afternoon. 

After the front passes, this will bring an end to the heat wave
and much welcomed change to the air mass, bringing temperatures
back to near seasonable norms. Next weekend looks to be dry and
comfortable as daytimes highs should return to the 70s and 80s 
and dewpoints will be back into the 50s. 




&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
Through 12Z Tuesday...Some localized 1-2SM BR expected at times
thru 11Z at SLK/MSS/MPV with very high low-level moisture. Will
see a return to VFR conditions for the balance of the daylight
hrs with south winds increasing to 10-12kt, and a few gusts to
18kt. Convective development is possible toward evening across
the nrn Adirondacks, spreading ewd across VT including BTV,
most likely 00-03Z. May see brief IFR conditions with localized
+TSRA. Light winds expected tonight, with possible BR/FG in
spots, especially with any TAF sites experiencing rainfall this
evening. 

Outlook...

Monday Night: VFR. Slight chance SHRA, Slight chance TSRA.
Tuesday: VFR. Slight chance SHRA, Slight chance TSRA.
Tuesday Night: VFR. Slight chance SHRA, Slight chance TSRA.
Independence Day: VFR. Slight chance SHRA, Slight chance TSRA.
Wednesday Night: VFR. Slight chance SHRA, Slight chance TSRA.
Thursday: VFR. Chance SHRA, Chance TSRA.
Thursday Night: VFR. Chance SHRA, Chance TSRA.
Friday: Mainly VFR, with local MVFR possible. Likely SHRA, Likely
TSRA.

&&

.CLIMATE...
Record Highs for July 1st through July 3rd

                      07/01       07/02      07/03

Burlington, VT      96|1931     96|1963   100|1911
Montpelier, VT      89|1968     90|1949    91|2002
St. Johnsbury, VT   98|1931     96|1963   101|1911
Massena, NY         93|1963     93|1963    95|1949
Plattsburgh, NY     94|1968     98|1963    98|1966
Saranac Lake, NY    95|1931     96|1931    96|1911

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Heat Advisory until 10 PM EDT this evening for VTZ003-004-
     006>008-010-016>019.
     Excessive Heat Warning until 10 PM EDT this evening for VTZ001-
     002-005-009-011-012.
NY...Heat Advisory until 10 PM EDT this evening for NYZ029>031-034.
     Excessive Heat Warning until 10 PM EDT this evening for 
     NYZ026>028-035-087.

&&

$$
SYNOPSIS...Banacos
NEAR TERM...Banacos
SHORT TERM...Banacos
LONG TERM...Verasamy
AVIATION...Banacos
CLIMATE...WFO BTV