textproduct: Burlington

WHAT HAS CHANGED

As of 248 PM EDT Sunday...

No significant changes.

KEY MESSAGES

As of 248 PM EDT Sunday...

1. Mostly quiet weather through tomorrow night.

2. Showers arrive Tuesday afternoon and evening, preceded by windy conditions.

3. No major impacts or significant weather expected late week into next weekend, as pattern continues to support unsettled conditions with below normal temperatures.

DISCUSSION

As of 248 PM EDT Sunday...

KEY MESSAGE 1: Weak ridging dominates through tomorrow night, bringing mostly dry weather. The exception is tonight, where a few scattered showers move through. They will be light with only a few hundredths of precipitation falling at most. These will be snow showers in the mountains where a light dusting is possible in the highest peaks. Temperatures will return to seasonable normals for Monday with highs in the 60s.

KEY MESSAGE 2: A cold front pushes into the region Tuesday afternoon and evening, bringing a line of showers. While a few scattered showers are possible earlier, the organized precipitation looks to enter northern New York in the afternoon and Vermont in the evening. Enough heating looks to occur ahead of it that CAPE values rise to around 250 to 500 J. The limiting feature for storm development will be moisture, with surface dew points looking to be in the 40s and low 50s at the time of the precipitation's arrival. While there is abundant deep layer shear, due to the limited instability, strong to severe storms currently look unlikely, though a few rumbles of thunder are possible. The area to watch would be if something develops along a pre-frontal trough in the afternoon, something akin to what the NAM3 has, though its dew points currently look too high. However the scenario will be watched as it enters the range of the other CAMs. Widespread showers should occur Tuesday night as the front slows down across the region, but by that point, the precipitation should be mostly stratiform and synoptically forced. Out ahead of the precipitation, a strong southwesterly low-level jet moves overhead. Gusts in the 25-35 mph look likely, with locally higher values possible in the St. Lawrence Valley and northern Adirondacks due to channeling and downsloping.

KEY MESSAGE 3: Not much change from the previous long term outlook as the trend of a less phased and progressive trough passage continues for mid to late week. Ridging across the western CONUS will lead to positively tilted troughing across the Northeast CONUS with several embedded shortwaves. Phasing between a northern stream of energy and a southern stream of energy riding up from the central Plains continues to trend unlikely with a more eastward shift to the central axis of moisture. The NAEFS ensemble denotes this well with moisture anomalies more centered over New Hampshire and southern New England. Regardless, shortwave passages will trend temperatures cooler for the later portion of the week with the coolest day based on thickness values and 925 to 850 mb thermal profiles likely on Friday. Daytime highs will be in the upper 30s to near 40 for summits and in the low to mid 50s for the wider valleys. Precipitation chances, regardless of system phasing, WPC still appears to denote chance pops in the higher terrain and chance pops in the valleys which is reasonable given cooling aloft and low level instability which should garner some isolated to scattered showers through the end of the week. This, however, does show a slight trend down in PoPs from previous runs, showing the uncertainty of the late week systems. Given the lack of strong high pres directly overhead and the potential for clouds, the probability of widespread frost in areas where the growing season has started is low attm.

AVIATION /00Z MONDAY THROUGH FRIDAY/

Through 00Z Tuesday...Mostly quiet weather forecast through Monday night. Widespread VFR conditions expected for the next few hours with ceilings around 6500-8500 feet above ground level or higher. Winds are a mixed bag this evening as mixing slows and stops, though some sites are still reporting some westerly winds. Winds will gradually shift out of the south- southwest overnight this evening as warm air advection and an upper level shortwave arrive across the region tonight. This is also expected to lower ceilings to around 2500-3500 feet and bring an increased chance for showers (visibilities likely 4-6 miles or higher) around 03Z-12Z Monday at all sites except MPV and RUT, which should be largely missed by precip and low level moisture over the next 24 hours. A modest west- southwesterly low level jet will also accompany the influx of warmth and moisture, resulting in likely LLWS at all sites except BTV and EFK, though it is still not out of the question at these sites, either.

Surface winds will also increase out of the south and southwest around 09Z-16Z Monday onwards with gusts 15-30 knots anticipated by Monday afternoon, highest across northern New York (more directly under the jet). A second round of MVFR ceilings is possible Monday morning and afternoon associated with a warm frontal boundary. Precip chances are slightly lower with this round. For SLK, the break between these two MVFR ceiling periods is expected to be brief or even non- existent. But for BTV, ceilings may lean more VFR and occasionally dip into MVFR territory with the passage of the shortwave, then the front. Most likely period for cigs 2500-3500 feet with the front will be 12Z through 19Z Monday.

Outlook...

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

BTV WATCHES/WARNINGS/ADVISORIES

VT...None. NY...None.