Marine Weather and Tides
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 6:46AM||Sunset 6:55PM||Thursday September 23, 2021 11:39 AM MDT (17:39 UTC)||Moonrise 8:25PM||Moonset 9:18AM||Illumination 95%|
7 Day Forecast for Marine Location Near Raymer (New Raymer), COHourly EDIT Help
Area Discussion for - Denver/Boulder, CO  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS65 KBOU 231603 AFDBOU
Area Forecast Discussion National Weather Service Denver/Boulder CO 1003 AM MDT Thu Sep 23 2021
UPDATE. Issued at 945 AM MDT Thu Sep 23 2021
Smoke from ongoing wildfires in California is faintly visible across the region, and added some color to the sunrise this morning. Near-surface concentrations are minimal, with most of the smoke hanging out aloft. Stronger winds aloft have also been producing some photogenic wave clouds along parts of the Front Range, as high cloud coverage begins to increase ahead of an approaching shortwave.
Temperatures today will be a few degrees warmer in the plains, where highs will climb into the low to mid 80's, with little change in the high country. A weak surface front is progressing southward east of the mountains, but aside from a slight increase in winds and elevated fire weather conditions in the plains, it will have little effect on our weather.
By mid afternoon, there could be enough mid-level moisture and lift to generate a few elevated showers in the high country, mostly for Summit and Park counties. But, with very dry conditions persisting near the surface, only virga and a few brief and light showers are expected, along with locally gusty outflow winds.
SHORT TERM. (Today and tonight) Issued at 335 AM MDT Thu Sep 23 2021
There will be an increasing, generally westerly flow aloft today ahead of an approaching shortwave. A dry, cool front will move over the plains in the afternoon and breezy northerly winds behind the front with low humidity will mean elevated fire danger on the northern plains. High temperatures will be similar to those yesterday in the high country, and a few degrees warmer across the plains. There may be just enough energy and moisture as the shortwave moves over Colorado this evening for isolated, very light showers on the Front Range mountains. The lower elevations should remain dry though there might be a few sprinkles around Park County, and gusty winds are possible with passing virga.
Low temperatures tonight should also be similar to those last night, though a bit cooler in the foothills and adjacent plains as subsidence over the Front Range decreases and resulting warm, downslope winds relax. By Thursday morning, the shortwave should be in the process of dropping a cutoff low over the Desert Southwest as it exits to the plains.
LONG TERM. (Friday through Wednesday) Issued at 335 AM MDT Thu Sep 23 2021
Dry and warm conditions will be the rule through early next week. Friday's temperatures on the plains will be a little cooler (but near normal) thanks to weak upslope and cool low level advection. However, that will change this weekend with weak lee troughing, downslope, and warm advection aloft. Those ingredients will support high temperatures well above normal, with readings approaching 90F across the plains by Sunday. The record for Denver is 90F, and we should be close to that.
There is still good agreement that the dry and unseasonably warm weather will persist through Monday and Tuesday with the blocking ridge developing over the Central High Plains. The operational GFS was an outlier solution per latest ensemble data, showing a faster arrival of the next short wave. We can't totally rule out enough moisture sneaking into the mountains for a few late day showers/storms by Tuesday, although we think at this point that would be a rush. We should see a better chance toward Wednesday and Thursday of next week. That's when the blocking pattern could weaken or shift slightly east as an upstream kicker moves across the Pacific Northwest. There are actually a few members bringing a decent amount of rain into the plains for the latter portion of next week, so at least something to watch over the next several days.
AVIATION. (For the 18Z TAFS through 18Z Friday afternoon) Issued at 945 AM MDT Thu Sep 23 2021
VFR conditions are likely to prevail through the TAF period. There will be some smoke aloft today, but concentrations are low, so the possibility of slant visibility issues will be slight. Surface visibility should remain unrestricted. Expect increasing high clouds at/above 20,000 ft MSL through the day.
A weak surface front will push through the terminals near 18Z, +/- 1 hour, bringing north/northeast winds with gusts to around 15 knots. Winds will weaken in the evening, returning to drainage overnight.
FIRE WEATHER. Issued at 335 AM MDT Thu Sep 23 2021
Elevated to briefly critical fire danger is expected on the northern plains Thursday afternoon. A surface front will bring breezy northerly winds gusting between 25 and 30 mph by mid afternoon, coincident with minimum humidities down to 10 to 15 percent. Fire danger will decrease quickly through the evening as winds relax and humidity increases.
Dry and unseasonably warm conditions will keep fire danger elevated this weekend through early next week. Sunday may see critical fire conditions over the Cheyenne Ridge and northern foothills as wind gusts near 25 mph combine with humidity under 15%. Very low humidity readings and poor to moderate humidity recovery will remain in the forecast through Tuesday, although winds are expected to be relatively light under a ridge of high pressure. Some increase in humidity is expected toward the middle of next week.
BOU WATCHES/WARNINGS/ADVISORIES. None.
UPDATE . Rodriguez SHORT TERM . EJD LONG TERM . Barjenbruch AVIATION . Rodriguez FIRE WEATHER . EJD/Barjenbruch
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|Greeley, Greeley-Weld County Airport, CO||37 mi||44 min||SW 4||10.00 mi||Fair||71°F||33°F||25%||1018.1 hPa|
Link to 5 minute data for KGXY
Wind History from GXY (wind in knots)
|1 day ago||NW||W||Calm||S||Calm||Calm||Calm||Calm||NE||E||N||N||W||NW||NW||Calm||Calm||Calm||Calm||S||S|
|2 days ago||N|
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