textproduct: Burlington

WHAT HAS CHANGED

As of 709 PM EDT Friday...

Adjusted rain chances to follow the latest radar trends. A few thunderstorms remain in the Northeast Kingdom, but they have been garden variety. The Heat Advisory currently in effect will be expiring shortly.

KEY MESSAGES

As of 300 PM EDT Friday...

1. Strong thunderstorms possible this afternoon and evening and again on Sunday.

2. Cooler for much of next week with a few shower chances.

DISCUSSION

As of 300 PM EDT Friday...

KEY MESSAGE 1: The Heat Advisory remains in effect till 8 PM for the Champlain Valley in Vermont and New York as well as the lower Connecticut River Valley where the highest heat indices are expected. Slightly cooler air will filter in behind a cold front for this weekend. High temperatures on Saturday and Sunday will only be in the 80s with dewpoints down in the 50s instead of the 60s. Another cold front will move through on Sunday which will bring much more seasonal air to the region to start the week with high temperatures in the upper 60s to mid 70s on Monday. On Sunday, a stronger cold front will move through during the afternoon hours and bring an abrupt pattern change to more seasonal temperatures. The strong thermal gradient associated with the cold front will yield strong frontogenesis/convergence along the frontal boundary and help interact with a sufficiently unstable air mass with more deep layer shear than is present today. The AI models and machine learning algorithms are actually flagging Sunday to be the more active severe weather day which fits the conceptual model of a strong change in air mass equating to stronger thunderstorms.

KEY MESSAGE 2: Large scale troughing will be established over the region for much of next week, bringing seasonably cool temperatures and several rounds of shower chances as shortwaves pivot around the longwave. Diurnal heating will help increase the shower chances in the afternoon a bit due to the cool air aloft. However, most of the time it will be dry. There is the potential for a more organized area of low pressure to move through late next week, likely sometime in the Thursday timeframe. GEFS, EPS and CMCE combined ensemble probabilities of more than an inch and two inches of total rain are 60-90 percent and 10-30 percent respectively. The rounds precipitation currently look to be light enough and moving quick enough to prevent much of a flooding threat.

AVIATION /00Z SATURDAY THROUGH WEDNESDAY/

Through 00Z Sunday...VFR conditions are expected for the next 24 hours. A few thunderstorms remain just east of KEFK. Outside a few high clouds, skies will generally trend clear. In spite of clear skies and recent rain, 15-25 knot winds are expected around 500-1500 ft agl. Though it may not result in LLWS, it will likely be turbulent overnight, and this will likely inhibit fog. Surface winds also will generally remain southwest to west at 5 knots. Some variability is possible where terrain influences will compete with synoptic flow, like at KRUT. These winds largely remain into the Saturday, with speeds 5-10 knots and gusts 15-20 knots. There could also be some competing factors for wind at KPBG in the afternoon as well. Winds will abate near or after 00z Sunday.

Outlook...

Saturday Night: VFR. NO SIG WX. Sunday: Mainly VFR, with local MVFR possible. Definite SHRA, Slight chance TSRA. Sunday Night: Mainly VFR, with areas MVFR possible. Chance SHRA. Monday: VFR. Slight chance SHRA. Monday Night: VFR. NO SIG WX. Tuesday: VFR. NO SIG WX. Tuesday Night: VFR. NO SIG WX. Wednesday: VFR. Chance SHRA.

CLIMATE

Record High Temperatures:

June 12: KBTV: 94/2017 KMPV: 88/2017 KPBG: 94/2017 KMSS: 89/2005 KSLK: 90/1933

Record High Minimum Temperatures:

June 12: KBTV: 71/2017 KPBG: 67/2017 KSLK: 62/1996

BTV WATCHES/WARNINGS/ADVISORIES

VT...Heat Advisory until 8 PM EDT this evening for VTZ001-002-005- 009-011-021. NY...Heat Advisory until 8 PM EDT this evening for NYZ028-035.