Marine Weather and Tides
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
|Sunrise 5:37AM||Sunset 9:14PM||Saturday May 30, 2020 1:56 AM MDT (07:56 UTC)||Moonrise 12:41PM||Moonset 1:47AM||Illumination 57%|
7 Day Forecast for Marine Location Near South Hills, MTHourly EDIT Help
Area Discussion for - Great Falls, MT  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS65 KTFX 300547 AFDTFX
Area Forecast Discussion National Weather Service Great Falls MT 1140 PM MDT Fri May 29 2020
Updated Aviation Section.
Main update this evening was to mostly remove mention of showers and thunderstorms. A few storms developed over Southwest Montana the last few hours, but they have since diminished or moved out of the forecast area. Analysis still shows weak instability across the area, but it will continue to decrease with the loss of daytime heating, and the disturbance responsible for the thunderstorm initiation has moved out of the area. Otherwise, the remainder of the forecast appears to be in good shape. Coulston
High pressure aloft will help warm temperatures to between 10 and 20 degrees above normal through the weekend. A few thunderstorms with strong wind gusts and small hail over Southwest Montana should diminish this evening, but another, more widespread round of thunderstorms is possible Saturday afternoon and evening, with the potential for damaging wind gusts and large hail. A breakdown of the ridge next week will likely keep temperatures about 10 degrees above normal with an increased chance for showers and thunderstorms once again during the mid to late week period.
AVIATION. Updated 1140 PM MDT Fri May 29 2020 (30/06Z TAF Package)
VFR conditions will mostly continue through Saturday morning across North Central, Central, and Southwest Montana. A few thunderstorms with erratic wind gusts and brief heavy rain are possible Saturday afternoon/evening. This could bring periods of MVFR conditions to the southwest and central Montana terminals Saturday afternoon and evening. Winds will remain breezy over the plains, becoming gusty after 18Z tomorrow. -TP
NOTE: Amendments not scheduled for Ennis (KEKS) due to ongoing runway closure.
PREV DISCUSSION. /ISSUED 650 PM MDT Fri May 29 2020/
This afternoon through Saturday Night . Moisture moving through a high pressure ridge will likely keep high clouds over North Central Montana through this evening. However, a weak disturbance in the weak westerly flow aloft will move over Southwest Montana this evening, likely causing a few thunderstorms to develop over the mountains. A dry airmass at the surface will keep the main threat from these storms being strong wind gusts (possibly up to 60 mph or so) from the stronger storms, but small hail is also possible. As the airmass stabilizes later this evening and overnight, storms will diminish and skies will clear. The high pressure ridge axis will then start to move east across the forecast area Saturday afternoon, causing the flow aloft to shift more southwesterly, which will increase lift and moisture over the area. However, lingering subsidence from the ridge will likely hinder thunderstorm development into the afternoon. The mostly clear skies will also allow temperatures to warm into the 80s for much of the area, which may enhance instability across the area. It is still uncertain whether this warming will be enough to break the cap aloft and allow significant convection (and subsequently strong to possibly severe thunderstorms with damaging winds and large hail) to develop. It is possible that this may not happen until early in the evening, when daytime heating is subsiding and therefore making significant convection less likely. As of now, though, will continue to message the threat for severe thunderstorms and see how things develop tomorrow. Am anticipating the storms to decrease late in the evening and overnight. Coulston
Sunday through next Friday . A disturbance in the southwest flow aloft will move over Western Montana on Sunday, which will keep a slight chance for showers over the area with slightly cooler temperatures than on Saturday. A broad and weak high pressure ridge with an anticyclonic westerly flow aloft will then move over the northern CONUS Monday and Tuesday. This will continue the breezy westerly winds and slight chance of showers with temperatures around 10 degrees above normal. However, a broad low pressure trough will then bring a more cyclonic westerly flow aloft for Wednesday through next Friday. Although this will likely not impact temperatures significantly (still looking at temperatures around 10 degrees above normal), the greater impact will be an increase in the chance for showers and thunderstorms across much of North Central and Southwest Montana.
PRELIMINARY POINT TEMPS/POPS. GTF 53 86 58 81 / 0 20 40 10 CTB 51 82 57 73 / 0 10 30 20 HLN 55 90 59 83 / 0 20 30 20 BZN 51 88 57 83 / 10 20 20 0 WYS 37 81 47 71 / 20 10 20 0 DLN 51 88 55 78 / 10 20 10 0 HVR 52 84 58 88 / 0 10 30 10 LWT 51 78 56 84 / 0 10 20 20
TFX WATCHES/WARNINGS/ADVISORIES. None.
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
|Helena Regional Airport, MT||3 mi||63 min||WSW 6||10.00 mi||Fair||63°F||50°F||63%||1017.1 hPa|
Link to 5 minute data for KHLN
Wind History from HLN (wind in knots)
|1 day ago||W||W||W||W||W||NW||N||Calm||Calm||N||NE||N||NE||N||N||N||NW||W||W||Calm|
|2 days ago||NW||W||W||W||Calm||Calm||NE||W|
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GEOS Local Image of EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
Link to Loop
Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for Great Falls, MT (3,6,7,8)(on/off)  Help
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