Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 05/02/20

Area Forecast Discussion
National Weather Service Honolulu HI
352 PM HST Fri May 1 2020 .SYNOPSIS... Strong high pressure north of the state will maintain gusty trade winds through the weekend. A stable atmosphere will relegate showers to mainly windward and mountain areas. A decaying cold front may weaken trade winds next week and increase shower coverage. && .DISCUSSION... Strong high pressure north of the state is maintaining gusty trade winds across the islands. The wind advisory that had been effect for portions of Maui County and the Kohala Mountains on the Big Island had been cancelled. Winds have dropped below the advisory threshold in those areas but remain gusty. Through the weekend, low clouds riding the trades will bring passing clouds and showers to mainly windward and mountain areas with a few quick showers reaching leeward areas of the smaller islands. The leeward Big Island will see increasing clouds in the afternoons with some embedded showers, and clearing skies at night. The current atmosphere is extremely stable with ridging aloft creating a strong temperature inversion near 6000 feet, as shown by both soundings from Hilo and Lihue. The upper ridge will maintain the stable atmosphere through Monday, relegating most of the showers to windward and mountain areas. Next week, a decaying surface front accompanied by an upper trough may increase island shower coverage and intensity by Wednesday, and decrease trade wind speeds. && .AVIATION... Surface high pressure north of the state will allow for moderate to occasionally strong east northeasterly trades continue this afternoon. This may create tempo moderate turbulence for aircraft on the leeward side of the mountains. Isolated showers will mainly affect windward portions of the islands over the next several hours. By tonight, expect an increase in cloud coverage and showers along the windward slopes and coasts with accompanying brief MVFR conditions. AIRMET SIERRA remains in effect for north thru east sections of Maui for tempo mountain obscuration above 2500 feet due to clouds and showers. AIRMET TANGO remains in effect for south thru west of mountains on all islands below 8000 feet due to moderate turbulence. && .MARINE... High pressure north and northwest of the state will help maintain fresh to strong trade winds through Monday. The trades will ease Tuesday and Wednesday next week as a trough sets up just north of the island chain. A Small Craft Advisory (SCA) remains in effect for most marine zones through Sunday due to the trade wind speeds. The SCA may need to be extended further for some coastal waters beyond Sunday. A series of north to northwest swells will move through the islands during the next week, keeping steady small to moderate sized surf in place along north and west facing shores. Surf along east facing shores will hold steady through the weekend, then lower a bit heading into the middle of next week as the trades ease. Small background southerly swells will continue along south facing shores through the middle of next week. Surf is expected to remain below advisory thresholds along all shores through the middle of next week. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Sunday for Kauai Northwest Waters-Kauai Windward Waters-Kauai Leeward Waters-Kauai Channel- Oahu Windward Waters-Oahu Leeward Waters-Kaiwi Channel-Maui County Windward Waters-Maui County Leeward Waters-Maalaea Bay- Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...Morrison AVIATION...Thomas MARINE...Foster
Area Forecast Discussion
National Weather Service Great Falls MT
855 PM MDT Fri May 1 2020 .UPDATE... For the most part, inherited forecast is tracking well. Saturday at 18Z, increased POPs slightly along our border to come in line with surrounding offices. Then increased POPs across Southwest Montana to allow a minimal increase in moisture, especially in the mountains, about 3 hours earlier than the previous shift forecast. After that, interpolated the next two hours up to 21Z, allowing for a smooth transition to a chance of moisture in some areas of the Southwest, and one that lines up nicely with the forecasts of our bordering Weather Forecast Offices. Tweaked Sky conditions just a bit, and reran QPF, etc.. Additionally, increased our chance of thunderstorm, slightly during the time period, Saturday 18Z to 00Z Sunday, keeping chance of thunderstorm at slight chance or less, but still better conveying current analysis and model guidance, while aligning well with our Forecast Office Neighbors. No changes to temperatures, humidity or winds, at this time. - Fogleman && .SYNOPSIS... A few light rain showers will affect North Central MT early this evening, otherwise expect quiet weather conditions through early Saturday afternoon. Then another round of showers and stronger winds will move through the region from Saturday evening through Sunday. Temperatures will cool a bit early next week, with more showers or thunderstorms possible by late next week. && .AVIATION... Updated 603 PM MDT Fri May 1 2020 (02/00Z TAF Period) Expect VFR conditions throughout this TAF period at all airfields with one exception. After 03/00Z KBZN is forecast to become MVFR, 4SM -SHRA BR, intermittently. Additionally, expect mountain obscurations along The Divide and in Southwest Montana beginning around 03/00Z. At the onset of this TAF period, gusty winds up to 24KT are forecast for KCTB, KHLN and KGTF, with periods of winds gusting to 18KTS at KEKS. These winds will impact light aircraft mostly near mountains and in passes. For details on ICG, TURBC and more, please see: - Fogleman NOTE: Amendments not scheduled for Ennis (KEKS) due to ongoing runway closure. && .PREV DISCUSSION... /ISSUED 603 PM MDT Fri May 1 2020/ Tonight through Sunday...With some cold air aloft over North Central MT this afternoon, the airmass has become a touch unstable, allowing for a few light rain showers to develop over North Central MT. Most of these showers should diminish by 7 PM, and any precipitation amounts this evening will be light. It is a quiet start to the day on Saturday, but the next upper level disturbance arrives over the western portions of the region by late Saturday afternoon. A few showers/isolated thunderstorms will accompany this disturbance. The precipitation continues into Sunday, as a cold front moves through the region. Surface winds will also increase, especially along the front range of the Rockies and around Cut Bank, but overall wind speeds should remain just below warning criteria as of now. Monday through Friday...Several weather disturbances will try to move through the region during the middle to later portions of next week. Overall confidence in timing/strength of each system is still a bit uncertain, as each model has a slightly different solution. Thus, the overall blend of the NBM model seems to have a good handle on temperatures/pops in much of the extended, with little changes made. Brusda && .PRELIMINARY POINT TEMPS/POPS... GTF 34 70 43 60 / 0 10 20 30 CTB 33 67 42 55 / 0 10 20 20 HLN 37 70 42 60 / 0 20 20 40 BZN 35 69 40 61 / 0 20 30 70 WYS 26 60 30 54 / 10 20 30 70 DLN 35 67 40 57 / 0 20 20 60 HVR 39 70 44 66 / 0 0 20 40 LWT 35 65 42 60 / 0 10 20 60 && .TFX WATCHES/WARNINGS/ADVISORIES... None. && $$