Thursday, September20, 2018 L-36.com


Marine Weather and Tides
Big Sky, MT

Version 3.4
What's New / NOTES
9/17/2018 XTide broke when 1and1 "upgraded" my server. It has been esculated. I am sorry for the problem.

Sunrise 7:08AMSunset 7:25PM Thursday September 20, 2018 3:02 AM MDT (09:02 UTC) Moonrise 4:40PMMoonset 1:32AM Illumination 79% Phase: Waxing Gibbous; Moon at 10 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
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7 Day Forecast for Marine Location Near Big Sky, MT
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location: 45.26, -111.31     debug


Area Discussion for - Great Falls, MT
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Fxus65 ktfx 200552
afdtfx
area forecast discussion
national weather service great falls mt
1150 pm mdt Wed sep 19 2018
aviation section updated

Update
Most of the forecast through Thursday morning remains valid.

However, adjusted pops and QPF to better match our neighbors'
changes. A swath of rain apparently tied to the trowal of a 700 mb
low pressure center will move from southwest mt this evening and
early Thursday morning to eastern parts of north-central mt over
the course of Thursday morning. In addition, deep lift ahead of a
mid- to upper-level pacific disturbance will trigger additional
rain, especially over eastern portions of north-central mt during
the course of this evening into Thursday morning. Thus, the
greatest rainfall through Thursday morning (i.E. 0.10 to 0.40
inches) is expected over blaine and fergus counties, as well as
far-eastern parts of judith basin, chouteau, and hill counties.

Lastly, elevated instability has permitted the development of a
few thunderstorms over southwest mt. This activity should wane
shortly after midnight tonight as instability weakens and is
consumed by ongoing storms.

- jaszka

Synopsis
Low clouds with areas of mid-elevation fog remain over the area
this evening. Rain showers will spread from southwest to northeast
overnight through early Thursday. Periods of rain continue at
times on Thursday, with snow levels dropping to near 7000 feet.

Areas of frost are likely under clearing skies early Friday. Fair
and seasonably cool weather prevails through the weekend.

Aviation
Updated 0550z.

Light rain and isolated thunderstorms continues to move
northeastward through the region. Expect the rain to exit the
havre lewistown areas around mid day Thursday. Low ceilings and some
patchy fog likely in the wake of ending rainfall. Scattered
showers isolated thunderstorms to affect areas from cut bank to
havre on Thursday afternoon. Expect mountains passes to be obscured
through the period. Overall expect ifr conditions through mid day,
with some lifr conditions at times. Brusda

Prev discussion
Issued 303 pm mdt Wed sep 19 2018
southwest montana enjoyed mild and dry conditions today, generally
south of interstate 90. Further north, cool and stable airmass
maintained widespread low clouds with areas of fog and drizzle
over mountain passes. A band of rain showers formed to the north
and east of lewistown associated with southerly mid-level winds
lifting over the shallow air mass. This sets the stage for the
next round of overnight precipitation across the region.

Satellite imagery shows developing cumulus over the southwest
mountains. Rain showers with a few rumbles of thunder are expected
to continue developing in this area through the evening. Areas of
rain become more widespread as a rather high amplitude trough
crosses rocky mountains through early Thursday. Cloudy conditions
will persist until winds switch to westerly behind the departing
trough on Thursday.

Today's forecast guidance moves this primary wave out into
eastern montana earlier than previous forecasts. However, a new
feature has emerged as a smaller shortwave trough ejects from
southern british columbia and crosses north-central montana
Thursday afternoon. Thus, even after a break in rainfall mid-day
Thursday, additional rain is possible Thursday afternoon. The
highest rain amounts are expected along and east of a line from
lewistown to havre where 0.5 to 0.8 inches are possible through
Thursday night. In southwest montana, weather conditions will
improve by mid-day with seasonally cool temperatures.

Clearing skies overnight Thursday enable a frosty morning for many
areas early Friday. Fair weather follows for most areas through
the weekend under a dry westerly flow aloft. A few showers will be
possible along the international border. Beyond that, another cold
front is expected to move southward into the region early next
week, but again precipitation amounts do not look overly heavy at
this time. Some mountain snow is possible next week, with lower
elevations generally averaging about 5 to 10 degrees below normal.

Preliminary point temps pops
Gtf 41 56 36 67 40 60 30 10
ctb 38 56 34 62 20 80 30 20
hln 44 61 39 70 40 30 10 0
bzn 42 60 36 70 60 50 10 0
wey 32 57 27 63 20 20 0 0
dln 38 60 33 69 80 30 0 0
hvr 42 54 37 65 70 80 30 10
lwt 39 50 34 65 70 70 20 0

Tfx watches warnings advisories
None.

Http:

Weather Reporting Stations
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Bozeman, Gallatin Field, MT38 mi67 minESE 710.00 miLight Rain46°F43°F89%1014 hPa

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Last 24hrSW6SW4SW5SW8SW4CalmW7W4W34NW7W6W5SW7SE12S10SE5S6S6SE5S6SE6SW5SE7
1 day agoCalmS5CalmCalmNE3S5Calm3N435NW5NW8N5W6W8NW6NW8CalmS8W5NW7SW5SW6
2 days agoSW4CalmS3SE7S6SE3S5S33Calm4NW8N5NW8N5NW4CalmS5SW8SW11N3W3CalmNE7

Tide / Current Tables for
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Tide / Current Tables for
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Weather Map and Satellite Images
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GOES 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.
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Wind Forecast for Great Falls, MT (5,6,7,8)
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Ground Weather Radar Station Billings, MT
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Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.