The 2nd longest heatwave in modern history (1900-onward) occurred across portions of NY and VT from June 18th through June 23rd. Temperatures exceeded 90 degrees for up to 6 consecutive days in portions of the Champlain and Connecticut River valleys.
Every event with a place to put it; 7 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS BTV wrote it up.
The 2nd longest heatwave in modern history (1900-onward) occurred across portions of NY and VT from June 18th through June 23rd. Temperatures exceeded 90 degrees for up to 6 consecutive days in portions of the Champlain and Connecticut River valleys. Daily High temperature records were set at Burlington on June 22nd and June 23rd with high temperatures of 96 for both days.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Burlington, VT wrote its last area forecast discussion before the first event at Jun 18, 9:21 AM EST, 39 minutes earlier.
Area Forecast Discussion National Weather Service Burlington VT 1021 AM EDT Thu Jun 18 2020 .SYNOPSIS... High pressure will continue to provide the North Country with much above normal temperatures and mainly dry conditions through Friday. The chances for showers and thunderstorms, along with relative humidity values increase this weekend into early next week. Temperatures will range in the mid 80s to lower 90s for highs and mid 50s to mid 60s for overnight lows, except cool back into the 80s by Sunday into Monday due to more clouds. && .NEAR TERM /THROUGH FRIDAY/... As of 1018 AM EDT Thursday...Going forecast remains on track and no changes were needed. High temperatures today still look to be near 90F with dewpoints in the mid to upper 50s. The near term fcst challenge will be areal coverage of convection on Friday, followed by temps. Water vapor shows a very stable/blocking type pattern with mid/upper lvl ridge axis acrs southern Canada, while closed cyclonic circulation is located near the VA/WV border. Deep dry layer/subsidence will result in plenty of sunshine again today with progged 925mb temps in the 21-23c range. This combined with very dry bl conditions should support highs mid 80s to lower 90s today with comfortable dwpt values. Tonight, a slight uptick in dwpt temps and the potential for mid/upper lvl clouds rotating into our fa, thinking lows hold in the mid 50s to mid 60s most areas. On Friday...weak embedded 5h vort from closed mid/upper lvl circulation over the mid Atlantic states rotates toward our fa. This feature combined with slightly better mid lvl moisture profiles and sfc based CAPE values in the 1200 to 1800 j/kg range will help in the development of trrn forced convection. Have continued to mention 20 to 30% pops for the northern dacks into portions of the mtns of central/northern VT btwn 16z-22z Fri. Soundings indicate very light flow <20 knots thru 300mb, supporting very slow storm motions and weak shear parameters. Thinking a variable storm motion of 5 to 10 knots is likely and probably driven off outflow type interactions. An axis of higher pw values near 1.50 inches arrives acrs our cwa on Friday, which combined with the taller/wider CAPE profiles and EL around 40kft support the potential for isolated/localized heavy downpours. Also, given the large cape profiles and potential for precip loading aloft, an isolated wet microburst cannot completely be ruled out, but probability/threat is low given light wind profiles. Any convection will quickly decrease in areal coverage/intensity by 00z with the loss of sfc heating/instability. Temps on Friday range from the mid 80s to lower 90s again, but should be slightly cooler in the mtns due to more cloud cover developing during the aftn hours. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... As of 332 AM EDT Thursday...Any lingering convection from Friday afternoon will come to an end Friday evening with the loss of diurnal heating. The upper level low over the Mid-Atlantic will begin pumping up moisture into the North Country with PWAT values increasing to as much as 1.5 inches by Saturday morning across southern Vermont. As a result, we will see dewpoints climb into the mid 60s. When you combine temperatures in the mid 80s to lower 90s with these higher dewpoints, you develop instability upwards to 1000 J/kg during the afternoon hours. The lack of forcing will once again keep shower and thunderstorm activity that fires up during the afternoon hours across the higher terrain. Brief heavy rainfall will be seen with the afternoon convection but once again it will taper off Saturday night with the loss of heating. The shower and thunderstorm activity Saturday afternoon should be more widespread given higher instability values present from 18Z-00Z. Lows both Friday night and Saturday night will be in the upper 50s to mid 60s with scattered clouds passing overhead as we continue to slowly advect additional moisture into the region. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... As of 332 AM EDT Thursday...A rinse and repeat of Saturday is expected again on Sunday with diurnal convection developing during the afternoon hours. Convection looks to be a little more widespread on Monday and Tuesday with a series of low amplitude upper level disturbances helping to invigorate afternoon showers/thunderstorms. We should begin increasing our steering flow aloft by Monday which will help move these showers and thunderstorms away from the higher terrain, thus PoPs for early to middle of next week are quite a bit higher than those this weekend. Models still diverge on the timing of a "cold" front midweek but the temperature change behind the front looks minimal with 850 mb temps decreasing from 16 C to 11C. Nevertheless, we should see a break in the higher humidity values behind the cold front midweek but until then highs in the mid 80s to lower 90s will be common. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... Through 12Z Friday...VFR conditions associated with high pres thru all layers of the atmosphere will continue today, along with light trrn driven winds of 3 to 7 knots. Tonight, soundings support the potential for some very shallow and localized fog/br to develop at SLK btwn 08z-10z again. Have not included in fcst, but will pass along info to dayshift on fog potential. MSS will need to be watched for some br toward sunrise on Friday with a 20 to 30 min period of mvfr possible. Outlook... Friday: VFR. Slight chance SHRA, Slight chance TSRA. Friday Night: VFR. NO SIG WX. Saturday: VFR. Slight chance SHRA, Slight chance TSRA. Saturday Night: VFR. NO SIG WX. Sunday: VFR. Slight chance SHRA, Slight chance TSRA. Sunday Night: VFR. Slight chance SHRA. Monday: Mainly VFR, with local MVFR possible. Chance SHRA, Chance TSRA. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && SYNOPSIS...Taber NEAR TERM...Hammond/Taber SHORT TERM...Clay LONG TERM...Clay AVIATION...Taber
Hazardous Weather Outlook National Weather Service Burlington VT 256 AM EDT Thu Jun 18 2020 NYZ026>031-034-035-087-VTZ001>012-016>019-190700- Northern St. Lawrence-Northern Franklin-Eastern Clinton- Southeastern St. Lawrence-Southern Franklin-Western Clinton- Western Essex-Eastern Essex-Southwestern St. Lawrence-Grand Isle- Western Franklin-Orleans-Essex-Western Chittenden-Lamoille-Caledonia- Washington-Western Addison-Orange-Western Rutland-Windsor- Eastern Franklin-Eastern Chittenden-Eastern Addison-Eastern Rutland- 256 AM EDT Thu Jun 18 2020 This Hazardous Weather Outlook is for northern New York, central Vermont, northeast Vermont, northwest Vermont and southern Vermont. .DAY ONE...Today and tonight. No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
The national radar mosaic for the moment the first event began.
8 heat. Local standard time, as filed.
High temperatures in the upper 80s to mid 90s for many parts of the Champlain Valley for six days with increasing humidity on the tail end of this stretch, bringing heat indices into the mid to upper 90s.
High temperatures in the upper 80s to mid 90s for many parts of the Champlain Valley for six days with increasing humidity on the tail end of this stretch, bringing heat indices into the mid to upper 90s.
High temperatures in the upper 80s to mid 90s for many parts of the Champlain Valley for six days with increasing humidity on the tail end of this stretch, bringing heat indices into the mid to upper 90s.
High temperatures in the upper 80s to lower 90s for the deeper valleys of the Connecticut River Valley for six days.
High temperatures in the upper 80s to lower 90s for the deeper valleys of the Connecticut River Valley for six days.
High temperatures in the upper 80s to lower 90s for the deeper valleys of the Connecticut River Valley for six days.
High temperatures in the upper 80s to mid 90s for many parts of the Champlain Valley for six days with increasing humidity on the tail end of this stretch, bringing heat indices into the mid to upper 90s.
High temperatures in the upper 80s to mid 90s for many parts of the Champlain Valley for six days with increasing humidity on the tail end of this stretch, bringing heat indices into the mid to upper 90s.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Vermont in 2020Every state in 2020This day in weather historyWarnings in Vermont, June 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 889564, 889566, 889567, 889568, 889569, 889570, 889571, 889572.