076 FXUS61 KBTV 100743 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 343 AM EDT Wed Oct 10 2018 .SYNOPSIS... Unseasonably warm weather will continue today before a cold front backs south and west into the region this evening. Another, stronger cold front will cross the area on Thursday with a widespread, wetting rainfall expected. Behind this front, much cooler and drier weather are expected by the upcoming weekend as Canadian high pressure settles into the region. && .NEAR TERM /THROUGH THURSDAY/... As of 343 AM EDT Wednesday...Changeable weather remains in store for our region over the next 36 hours. As of early morning we remain firmly in an unseasonably warm airmass on the northern periphery of deep subtropical ridging across the eastern third of the nation. Temperatures remain extremely mild by early October standards, running from the mid 60s to lower 70s as of 300 am. The warm front that lifted through the region yesterday morning currently lies across southern ON/QE and eastward into northern Maine. Nearly all guidance continues to show this boundary sagging southward today in response to a passing shortwave trough to our distant north. Using a blend of WRF 4km and NAM 3km output suggests this boundary will push south and west into far northern counties later this afternoon, and into eastern VT this evening/tonight where it will stall. Areas across the Adirondacks, southern SLV and southwestern VT will likely remain to it's south and west. Hourly temperature trends and resultant 12-hr maxima will be tricky, though in general readings should climb to quite warm readings through early to mid afternoon before readings begin to fall sharply across the far north late. A few spots may once again near record territory as values in general top out from 72 to 78 with a few spots nearing the 80F mark in the SLV/Champlain Valleys. Forcing for precipitation in most of the area will remain weak today, especially central/south. The highest threat of any showers and perhaps a widely scattered storm will occur across the far north in proximity to the approaching boundary, though even here only slight chance to chance values will be offered as instability and forcing will be rather limited. By tonight the aforementioned front backs into eastern VT while slowly lifting northward from the northern SLV/Champlain Valleys in reponse to deepening southerly flow ahead of a seasonably deep longwave trough and stronger cold front marching east from the Great Lakes. Temperatures will once again be quite a challenge given the airmass change across the boundary. Temperatures in the 50s to lower 60s across the far northern SLV/Champlain Valleys to slowly moderate over time as the front lifts out. Meanwhile, readings fall into the 50s with some patchy drizzle possible in eastern VT as the eastern portions of the front backs westward with a maritime-modified airmass. Areas across far southwest VT into the Adirondacks remain mild in the 60s. Meanwhile, as the trough and surface front approach, precipitation chances ramp up sharply from west to east after midnight with a steady light rain evolving across western counties toward dawn on Thursday. As such likely to categorical PoPs will be maintained from east to west after 200 am accordingly. By Thursday the main frontal boundary swings through the region with a widespread and wetting rainfall expected. Temperatures remain seasonably mild as low level flow trends south/southwesterly in all areas. Coolest readings are expected across eastern VT in the slowly eroding maritime airmass (upper 50s/lower 60s) with somewhat milder readings from the Champlain Valley west (mid 60s to around 70). As the front begins to push into far eastern counties later in the day a gradual decrease in precipitation coverage is expected across our far western counties by afternoon. 12-18 hr pcpn totals to generally average in the 0.50 to 0.75 inch range. && .SHORT TERM /THURSDAY NIGHT/... As of 319 PM EDT Tuesday...The warmer weather of Wednesday will be an afterthought come Thursday as a cold front and highly amplified mid-latitude trough come sweeping through the region. However, another day of temperatures in the 60s to near 70 degrees will be expected on Thursday prior to the passage of the cold front with 850 mb temperatures sitting at 13 to 15 degrees Celsius. Rainfall will be pretty showery around sunrise on Thursday with the northern periphery of the upper level ridge barely holding on ahead of the highly amplified trough. With the help of a strong mid-level and upper level jet, the cold front and frontal trough will quickly push into the North Country several hours after sunrise with rainfall quickly overspreading the region. Models continue to be quite optimistic with rainfall, which is entirely plausible given great southwesterly fetch of Gulf Moisture (PWAT values approaching 2 inches). Rainfall amounts will vary between a a half inch across northern New York to around an inch across southern and eastern Vermont. Instability will be rather limited given the timing of the precipitation but with temps and dewpoints in the 60s with temperatures cooling aloft (steepening lapse rates), a rumble or two of thunder is not out of the question. && .LONG TERM /FRIDAY THROUGH TUESDAY/... As of 319 PM EDT Tuesday...The aforementioned cold front will continue to push across the North Country Thursday heading into Friday morning with below normal temperatures expected in it's wake. The North Country will remain under the influence of the upper level trough which will advect a potent Canadian air mass which will usher in some of the coldest temperatures of the season to date. A reinforcing short of cold air will be seen on Saturday as the axis of the upper level trough pushes through the region. This should help Saturday be quite a bit colder than Friday as 850 mb temperatures drop to 0 to -5 degrees Celsius with the coldest values close to the international border. Friday night and Saturday night will see many locations drop into the 30s with some locations dropping into the mid to upper 20s. The Champlain Valley will once again be on the warm side with temperatures struggling to drop below 38 degrees Saturday night. While under the influence of the upper level trough, a series of shortwaves will track along the longwave pattern which will bring some rain and snow chances to the region. While it is hard to try and pin-point these showers, it won't be until Monday until the first chance for showers would be possible. By this time, temperatures aloft will have already begun to modify under the fall sun. However, it wouldn't be out of the question for parts of the North Country to see some termination dust on the higher peaks of the Adirondacks and Green Mountains with some of these showers. Any snow at higher elevations that does fall will melt given temperatures warmer aloft but another deep trough begins to set up across the central US on Wednesday. && .AVIATION /08Z WEDNESDAY THROUGH SUNDAY/... Through 06Z Thursday...VFR conds expected through 18Z at all terminals. Some patchy, though passing mid level cigs mainly in the 050-100 AGL level expected during this time frame with south to southwesterly flow from 3 to 8 kts expected (locally to 12 kts at KBTV). After 18Z a cold front will drop southward into far northern counties and stall as cigs trend MVFR and winds trend light north to northeasterly at KMSS/KPBG/KBTV. A few light showers will be possible in the vicinity of this boundary. Further south, winds remain light south/southwesterly at KRUT/KSLK/KMPV, though a gradual trend to MVFR cigs by 00Z or shortly thereafter is also expected. Some IFR possible at KMSS. Outlook... Thursday: Mainly MVFR, with areas IFR possible. Likely SHRA, Slight chance TSRA. Thursday Night: Mainly VFR, with local MVFR possible. Slight chance SHRA. Friday: Mainly VFR, with local MVFR possible. Slight chance SHRA. Friday Night: VFR. NO SIG WX. Saturday: Mainly VFR, with local MVFR possible. NO SIG WX. Saturday Night: NO SIG WX. Sunday: Slight chance SHRA. && .CLIMATE... Here are record high temperatures for today, October 10. DateKBTV KMPV K1V4 KMSS KPBG KSLK 10-10 81|1909 80|1949 74|2017 80|1970 81|1955 82|1909 && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...JMG NEAR TERM...JMG SHORT TERM...Clay LONG TERM...Clay AVIATION...JMG CLIMATE...JMG