Monday, June14, 2021
Privacy Policy
L-36.com

Marine Weather and Tides
South Hills, MT

Version 3.4
NOTICE
3/30/2021 -- ANZ330 has been split into ANZ331 and ANZ332. Click EDIT in Marine Forecast and select your new zone.
1/26/2021 -- The West Coast Satellite images havd been updated. They now use GEOS-17.
1/1/2021 -- The 7 day forecast are now working well. Thank you NOAA for your support.

Sunrise 5:32AMSunset 9:24PM Monday June 14, 2021 9:28 PM MDT (03:28 UTC) Moonrise 8:14AMMoonset 11:54PM Illumination 26% Phase: Waxing Crescent; Moon at 5 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
    EDIT      (on/off)   Help


7 Day Forecast for Marine Location Near South Hills, MT
   Hourly   EDIT   Help
location: 46.57, -112.02     debug


Area Discussion for - Great Falls, MT
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
FXUS65 KTFX 150243 AFDTFX

Area Forecast Discussion National Weather Service Great Falls MT 843 PM MDT Mon Jun 14 2021

SYNOPSIS.

Hot and mostly dry conditions will prevail across the Northern Rockies through Tuesday, but an approaching weather system will likely bring slightly cooler temperatures to western areas by Tuesday afternoon. The strong Pacific cold front brings falling temperatures and windy conditions for all areas on Wednesday. Record high temperatures will be in jeopardy of falling at numerous locations both today and on Tuesday as highs rise into the 90s to lower 100s.

UPDATE.

Very hot afternoon temperatures are gradually cooling across the region, but overnight lows will remain elevated and another hot day is on tap for Tuesday. Biggest concern this evening is isolated showers/thunderstorms moving through north central Montana. As expected, several storms developed over the western mountains and worked their way north-northeastward over the plains of north central Montana into Alberta. However, a few storms have also developed in eastern Fergus so have increased PoPs and sky coverage in this region. Models suggest that isolated to scattered convection could persist in eastern portions of the CWA overnight, but confidence on this is rather low at this time. Remainder of the afternoon forecast package is in good shape and no further updates are anticipated. mpj

AVIATION. 535 PM MDT Monday Jun 14 2021 (15/00Z TAF period)

Scattered mid-level cumulus clouds producing weak showers and a few lightning strikes will continue to affect portions of the forecast area this evening. Convection is developing over the mountains of southwestern Montana and is moving north-northeast through north central Montana into southern Alberta. Convective clouds and showers will diminish by 04Z Tuesday with mostly clear skies expected overnight. Southwesterly surface winds of 25 to 35 mph will develop across much of the forecast area by 18Z Tuesday as a dry surface cool front pushes into central Montana from the west. mpj

FIRE WEATHER.

Near record heat and low humidity will accelerate the drying of fuels early this week. Gusty southwest winds are expected Tuesday afternoon, particularly across southwest MT where afternoon humidity will fall to around 10-15%. Further north across north- central MT, humidity will not be as low today, but is expected to fall to 10-20% Tuesday afternoon as winds increase from the south and a wind shift to the west is likely late Tuesday or Tuesday night in association with a mainly dry cold front. The increase in winds in addition to the heat and dryness will raise fire weather concerns across the area and a Red Flag Warning has been issued for Tuesday for the south and eastern fire weather zones. The degree of drying and curing of fuels is less certain further north, but still need to be monitored for fire weather.

PREV DISCUSSION. /ISSUED 535 PM MDT Mon Jun 14 2021/

Remainder of this afternoon through Tuesday evening . The Northern Rockies continues to be situated on the western periphery of a strong high pressure ridge centered over Eastern MT. Another subtle shortwave embedded within the southwesterly flow aloft may bring another round of isolated thunderstorms for this evening. It doesn't appear to be as organized as yesterday and the best chance for storms will be along the Divide and over the higher terrain of Central/North-central MT. With that being said, any storm that does form will have the potential to produce strong and gusty winds, and cloud to ground lightning. Current mesoanalysis shows ML CAPE values of 500 to 1000 j/kg and DCAPE up to 2000 j/kg over the plains. This has likely lead to the SPC's thunder upgrade to a marginal risk for severe wind gusts over much of Central/North-central Montana later this afternoon and evening. Rainfall amounts will generally be less than 0.10". Afternoon temperatures are warming as advertised and will peak in the 90s to lower 100s for most lower elevations. The Heat Advisory for Hill, Blaine, Chouteau, and Fergus counties remains in effect as this is where high temperatures in the low 100s will be most widespread both today and on Tuesday. While other locations outside of this Heat Advisory are expected to reach into the upper 90s and low 100s today, they are not expected to do so on Tuesday and will remain excluded for the advisory.

On Tuesday the H500 ridge axis shifts further east as a longwave trough begins to dig in over the Pacific Northwest and Northern California. This will help to keep the hottest 100+ temperatures just east of our forecast area. However, Hill, Blaine, Chouteau, and Fergus Counties will see highs in the upper 90s to low 100s, and widespread highs in the low to mid-90s will still be common across much of the remainder of Southwest through North-Central Montana. Increasing low to mid-level south to southwesterly flow on Tuesday will lead to increasing surface winds across the entire region with diurnal mixing, especially in the north-south orientated valleys of Southwest Montana where terrain funneling will enhance speeds. Deep afternoon mixing through H700 to near H500 over Southwest Montana, where wind speeds of 35 to 55kts will be present, combined with the orientation of the wind to the terrain (terrain funneling) could produce a 6-9hr period (between noon and 9pm) of near High Wind criteria speeds and gusts across Beaverhead and Madison counties. Current thinking is that wind speeds will mostly stay in the 45 to 55 mph range and will likely be handled with a longer fused special weather statement tonight or early tomorrow. regardless, the situation will continue to be monitored. A Pacific cold front will then begin to move across Western Montana late Tuesday afternoon as a surface low develops over Northern Montana/Southern Alberta and quickly ejects northeast to Central Saskatchewan (Tuesday evening). This will bring a westerly wind shift and introduce, mostly over the plains. - Moldan/RCG

Tuesday night through next Monday . primary concern and focus will be on the potential for high winds on Wednesday.

The elevated Pacific cold front will quickly slide east and across the CWA Tuesday night, shifting winds to the west in addition to increasing speeds. While the strongest H850-700 winds will be present over Central and North Central Montana Tuesday night, questions about how deeply mixed the region remains during the overnight hours creates some doubts that high winds will materialize despite wind speeds of 35-55kts (H850-700). If these winds were able to mix down, believe that the Rocky Mountain Front, Eastern Glacier, and western portions of Toole County would be most at risk of seeing high winds given a moderate pressure gradient orientated along the Continental Divide and the potential for mountain wave activity given weak ridgetop stability. By Wednesday the H850-700 flow will begin to weaken to around 30-40kts, all the while shifting north to over the Hi-Line. While lower in overall speeds, deep mixing through these levels (along and north of the Hi-Line) Wednesday afternoon does raise concerns that some locations could reach High Wind criteria values on sustained wind speeds, especially given deep unidirectional flow through H700 combined with subsidence on the backside of the departing upper level shortwave. Have continued to hold off on issuing any High Wind highlights for this timeframe, but the situation will continue to be monitored by future shifts. While a few isolated to scattered showers and thunderstorms are possible along the Continental Divide Tuesday night with the passage of the Pacific cold front, the front as a whole will be fairly dry, only bringing a drop in temperatures for the day on Wednesday and through the remainder of the work week. - Moldan/RCG

PRELIMINARY POINT TEMPS/POPS. GTF 61 91 49 78 / 10 0 20 0 CTB 57 82 47 71 / 30 0 20 0 HLN 61 95 52 81 / 10 10 10 0 BZN 54 97 47 83 / 0 0 0 0 WYS 42 86 40 78 / 0 0 0 0 DLN 55 91 44 83 / 0 0 0 0 HVR 65 100 53 78 / 30 0 10 0 LWT 60 97 50 76 / 20 0 0 0

TFX WATCHES/WARNINGS/ADVISORIES. Red Flag Warning from 9 AM Tuesday to midnight MDT Tuesday night Central and Eastern Lewis and Clark National Forest Areas . Chouteau and Fergus Counties . Deerlodge/Western Beaverhead National Forest . Eastern Beaverhead National Forest . Helena and Townsend Ranger Districts of the Helena National Forest . Hill and Blaine Counties.

Heat Advisory until 8 PM MDT Tuesday Blaine . Chouteau . Fergus . Hill.

Red Flag Warning from 10 AM to 10 PM MDT Tuesday Gallatin National Forest.



http://www.weather.gov/greatfalls


Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports. Follow links for more data.
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Helena Regional Airport, MT3 mi36 minSSW 8 G 2010.00 miFair94°F25°F8%1007.7 hPa

Link to 5 minute data for KHLN

Wind History from HLN (wind in knots)
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
Last 24hrS5W9W8W9W8W6SW6N3CalmCalmCalmCalmN4CalmCalmN65NE7S12
G22
S12
G21
S15
G20
SW9
G17
SW7S8
G20
1 day agoW5W9W8CalmW10CalmW5SW3CalmNE3CalmCalm4Calm--N4N6E8
G16
E12
G23
E17
G23
E13
G20
E10
G22
W19
G29
SE4
2 days agoW6W5SW6N4CalmW6CalmCalmCalmCalmW4N3CalmCalmNW19
G26
W18
G23
W17
G25
W16
G25
NW21
G28
W14
G24
NW11NW10N9NW4

Tide / Current Tables for
   EDIT   Weekend mode (on/off)   (on/off)   Help
Tide / Current Tables for
   EDIT      (on/off)   Help
Weather Map
       (on/off)   Help Weather Map
wmap_P
GEOS Local Image of    EDIT
NOTE: This section has been updated as of 1/26/2021. If the image you are expecting is not showing, please let me know. You may use the EDIT function to update your location.
Link to Loop

Other links: GEOS-West     Contential US     Full GOES-East
Ground Weather Radar Station




Please read website Cookie, Privacy, and Disclamers by clicking HERE.