834 FXUS61 KBTV 261147 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 747 AM EDT Sat Jul 26 2025 .SYNOPSIS... Widespread smoke and haze is present in most of northern Vermont today, with otherwise seasonable temperatures and dry weather expected today. A couple of chances for rain and isolated thunderstorms exists late tonight into Sunday, as hotter and humid conditions persist through Tuesday. Conditions then trend substantially drier, with below normal temperatures expected during the later part of the week along with dry weather. && .NEAR TERM /THROUGH SUNDAY/... As of 316 AM EDT Saturday...Main story for today is the combination of fog and smoke early in the day, primarily east of the Adirondacks through much of northern Vermont. Smoke has been forced to the surface after it advected southward into the region and will probably not mix out very quickly given light winds. Model soundings show deep mixing developing towards noon which lead to some improvement during the afternoon. So expect degraded air quality, as of this writing in the unhealthy category for much of the aforementioned area, will linger. As such, the forecast shows mention of smoke into the daytime hours. At the very least, there will be haze today with otherwise sunny and dry conditions as the air mass otherwise will be rather pleasant. Light southerly flow will increase slightly towards evening. It remains a challenging forecast scenario for late tonight into tomorrow with two periods of shower and thunderstorm chances, each with fairly low predictability. Neither one looks particularly impactful with regards to potential for flash flooding or severe thunderstorms, but both threats will need to be monitored despite low risk. The early Sunday morning forcing for widespread showers with heavy rainfall, especially in embedded thunderstorms, still looks relatively straightforward; however, it remains uncertain how far north this area of rain will go as a strong upper level wave crosses the region from west to east. Several pieces of model guidance show heavy rain moving into the Adirondacks during the predawn hours and peeling slightly south of due east over the southern Green Mountains; generally chances of rain are higher as one goes southward. The environment will likely feature rich moisture supportive of heavy rainfall rates, but just to the north there will be a plethora of dry air aloft. A lot like a winter storm, there is a lot of spread in possible precipitation amounts. For instance, in Newcomb, New York where heavy rainfall is probably more likely than anywhere else in our forecast area, amongst model guidance the interquartile range of six hour precipitation ending 8 AM Sunday is from 0.1" to 0.77" with a few models showing 1 to 2.5" of rain. Footprints of 1-1.5" of rain within 6 hours are possible, with areas like Newcomb having about a 70% chance of reaching an inch of rainfall per the HREF guidance Ensemble Agreement Scale. Later in the day as temperatures warm into the 80s with dew points in the 65 to 70 range, we should see instability build. Per HREF- calibration chances of thunder, isolated to scattered thunderstorms across northern New York and western Vermont looks reasonable. That would be consistent with a surface weather pattern featuring a weak triple point feature in the St. Lawrence Valley and attendant warm front draped across the Champlain Valley. In the warm sector, instability should become moderately high, approaching 2000 J/kg Sunday afternoon, with a sharply lower amount of CAPE probable farther south and east. The possible trigger for convection may be a combination of another embedded trough coming across the region as flow aloft turns more northwesterly and topographically-enhanced convergence. This pattern does not suggest a heavy rain threat, but northwesterly deep layer shear and sufficient instability could support a gusty wind threat as DCAPE will probably be fairly high. It is unclear if storms will gain much organization, but we`ll monitor trends in the convective allowing models which currently show little predictability in what will transpire. && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY/... As of 316 AM EDT Saturday...This period will be characterized by seasonably hot and humid conditions as temperatures climb into the upper 80s to low 90s. Humid conditions in place Sunday will help temperatures stay mild such that we start the day with temperatures already in the mid to upper 60s in many locations. Right now the forecast does look slightly less impressive than this past Thursday as far as apparent temperatures, so while it would not be surprising to need Heat Advisories, it is not obvious that heat index values will exceed 95 anywhere. Ensemble anomalies for the upper levels are also not as impressive as the low level heat would suggest, which could support some diurnally driven convection. For now, PoPs are too low to include mention of thunderstorms, but that could be something to watch moving forward as a cold front, or pre-frontal trough, moves into the area and interacts with the likely moderately high instability over the region. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... As of 210 AM EDT Saturday...Warm, humid conditions are expected Monday night ahead of a cold frontal passage Tuesday morning. Expect upper 60s to lower 70s for the broad valleys and mid 60s in cool hollows. The front itself will cross with little fanfare as dry air and early timing keep activity scattered. Cold air will take a bit more time to displace the hotter air from Monday, and so another toasty day ranging from the mid 80s north to 90s south is again expected. There will at least be lower humidity filtering in. Wednesday will likely be a pleasant day with isolated to scattered showers and a few thunderstorms as temperatures climb into the mid 80s with upper 50s to lower 60s dewpoints. A thermally stronger cold front will slide south as an anomalously strong and cool upper low dives southwards. The front will again struggle with the moisture department, and the lack of a well-defined surface feature will prevent widespread activity in the absence of better instability which will reside well south of us. The rest of the extended will trend dry and cool as that upper low makes its approach. Several models depict sub-540 dam thicknesses from 1000-500mb and the 850mb 0 C line possibly grazing the Northeast Kingdom, which is very impressive for this time of year. Abundant sunshine and dry atmospheric conditions will likely allow efficient warming into the 70s, and a sustained wind due to modest pressure gradients will likely only produce somewhat below normal nighttime lows. This fall-like pattern may bear watching for dry relative humidity values against gusty northwest winds given many areas are running 2-5" below normal for precipitation this summer. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... Through 12Z Sunday...Skies will trend clear, but wildfire smoke will across the Champlain Valley and all of Vermont will be slow to depart leading to MVFR visibilities for at least the first few hours. Flow will be mostly terrain driven with upslope northwest winds likely at KRUT and KMPV, or southwest lake breezes at KBTV and southeast breezes at KPBG. Some element of variability may also develop as southwest winds try to become established, but after 00z, winds will trend light or terrain driven. Clouds will remain FEW to SCT at or above 10000 ft agl, although towards the end of the period clouds may lower in western portions of the airspace. Outlook... Sunday: Mainly VFR, with local MVFR possible. Chance SHRA, Slight chance TSRA. Sunday Night: VFR. NO SIG WX. Monday: VFR. NO SIG WX. Monday Night: VFR. Chance SHRA, Slight chance TSRA. Tuesday: VFR. Chance SHRA, Chance TSRA. Tuesday Night: VFR. Slight chance SHRA, Slight chance TSRA. Wednesday: VFR. Slight chance SHRA, Slight chance TSRA. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Kutikoff NEAR TERM...Kutikoff SHORT TERM...Kutikoff LONG TERM...Haynes AVIATION...Haynes/Kutikoff