Marine Weather and Tides
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.
6/2/2019. Many thanks to a user for reporting an error on one of the Edit pages. The switch to PHP 7.2 caused many pages that previously worked to quit working. I fixed many but I still depend on users to report ones I missed. Please report errors HERE or send an email to me at L-36.com. Allen
|Sunrise 7:12AM||Sunset 4:36PM||Sunday December 15, 2019 2:51 AM MST (09:51 UTC)||Moonrise 9:20PM||Moonset 11:20AM||Illumination 86%|
7 Day Forecast for Marine Location Near Lochbuie, COHourly EDIT Help
Area Discussion for - Denver/Boulder, CO  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS65 KBOU 150424 AFDBOU
Area Forecast Discussion National Weather Service Denver/Boulder CO 924 PM MST Sat Dec 14 2019
UPDATE. Issued at 921 PM MST Sat Dec 14 2019
With cloud cover disappearing over the urban corridor and parts of the plains, areas of fog have developed. Some stratus over the northeastern plains is slowly moving west, not expecting it to make it all the way into the urban corridor, at least into the Denver area as winds should return to drainage and then the northern push expected later today should bring in drier air to dissipate the stratus and fog.
UPDATE Issued at 620 PM MST Sat Dec 14 2019
Have decreased PoPs quicker this evening, especially over the plains, and decreased the coverage after midnight. May need to remove PoPs completely from the forecast area tomorrow morning as the next system is still digging into California. Most models have no precipitation in our forecast area until after noon - with little if any reaching the metro area . except for perhaps the southern sections but not until Sunday evening. Will wait for the 00z models to come in and see if the later trend continues.
SHORT TERM. (This evening through Sunday) Issued at 134 PM MST Sat Dec 14 2019
For this afternoon, moderate to heavy snow continues in the mountains with enhanced bands of locally heavy snow spreading out across the urban corridor and adjacent plains in the eastern Larimer, Morgan and Weld counties. Issued a snow squall warning to account for this with accumulating snowfall evident on highway cams. Expect much of this to diminish by this evening. No changes regarding the timing of the heavy snow through this evening. Most of the models show the snow intensity decreasing significantly after midnight. There should be another break in the weather late tonight into early Sunday. Latest models runs continue to drag the last part of this system further south during the day Sunday. The upper level jet will shift to the east of the state with a weaker zonal flow aloft. Another area of enhanced snowfall is progged to lift south to north into the forecast area mid morning Sunday and continue into afternoon. Snow for the Denver area continues to trend towards decreasing forecast amounts. Several runs do not even forecast snow in the Denver area. Best chance will be south of Interstate 70. Some concern of moderate snowfall for Park County however. Will issues a Winter Weather Advisory for South Park Sunday through Sunday evening.
LONG TERM. (Sunday night through Saturday) Issued at 134 PM MST Sat Dec 14 2019
By Sunday evening the upper trough will be closing in on the four corners region with flow turning more southwesterly over Colorado. Drier air will be moving in decreasing snow chances from the North to the South. Areas south of I-70 will continue to see light snow into the early morning hours on Monday as the upper trough and better jet dynamics push southeast. There is little respite as a weak shortwave embedded in the upper level WNW flow will push in during the day Monday bringing another round of light snow to the northern and central mountains. This will be more orographic-based as there is no jet support with it. Amounts will be on the lighter side with just an additional 1-3 inches across the higher elevations by Monday evening. The plains will remain dry with only a slight chance of light snow for areas south of I-70 along the Palmer Divide with weak upslope and minimal moisture. An additional trace to 1 inch is possible for those areas. Conditions will remain cool with highs staying right around freezing on the plains and teens to in the high country.
On Tuesday, upper level flow will turn more northerly and dry air will push in bringing snow to an end across the region. With the clearing Monday night into Tuesday lows will drop into the single digits across the lower elevations with below zero for the higher terrain and mountain valleys. Tuesday will be a slow warm up with the cold air inversions in place, but highs are expected to climb into the upper 30s to lower 40s under mostly sunny skies.
By mid-week an upper level ridge will build in bringing dry conditions Wednesday with temperatures warming into the upper 40s and possibly 50s. For Thursday, models start to diverge on the speed of an upper level trough that is forecasted to move onshore into California by Wednesday morning. The GFS has the system moving much faster than the EC and the low center further north. Both models show minimal moisture so will maintain a slight chance of snow for the higher mountains Thursday. The plains should remain dry but with some CAA temperatures will be a tad cooler than Wednesday.
AVIATION. (For the 18Z TAFS through 18Z Sunday afternoon) Issued at 620 PM MST Sat Dec 14 2019
Most shower activity is expected to be done over the airports, with some isolated showers further east and north along the state border. At this time, expecting VFR conditions, however low ceilings are expected to start moving in to the northeastern plains. Most models have it staying out, but just northeast of the TAF terminals, with some having it curl into BJC. So it could require close monitoring overnight. If it does make it in, ceilings of 200-400 feet will prevail with some patchy fog. Drainage winds should keep it out of the terminals however. Otherwise, a dry northerly surge will move down the plains after 10z to clear out the fog and stratus. Winds will veer around to the northeast through Sunday morning and afternoon, with another chance of snow moving in from the south late afternoon to evening, but expect accumulating snowfall to stay south of I-70.
BOU WATCHES/WARNINGS/ADVISORIES. Winter Weather Advisory from 8 AM Sunday to midnight MST Sunday night for COZ037.
Winter Storm Warning until 11 PM MST this evening for COZ031-033- 034.
UPDATE . Kriederman SHORT TERM . Cooper LONG TERM . Bowen AVIATION . Kriederman
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.
|Denver, Denver International Airport, CO||7 mi||58 min||N 0||9.00 mi||Partly Cloudy||26°F||23°F||88%||1007.8 hPa|
|Denver Nexrad, CO||14 mi||57 min||SW 3||10.00 mi||Partly Cloudy||28°F||26°F||92%||1007.1 hPa|
|Buckley Air Force Base Airport, CO||15 mi||1.9 hrs||S 5||10.00 mi||Mostly Cloudy||27°F||25°F||94%||1007 hPa|
|Erie Municipal Airport, CO||19 mi||57 min||N 0||0.25 mi||Freezing Fog||24°F||23°F||96%||1009.1 hPa|
|Broomfield / Jeffco, CO||22 mi||57 min||NNW 7||10.00 mi||Fair||27°F||21°F||80%||1007.1 hPa|
Link to 5 minute data for KDEN
Wind History from DEN (wind in knots)
|1 day ago||SW||SW||SW||SW||SW||SW||W|
|2 days ago||S||S||S||SW||SE||S||S||S||SE||NW||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 Denver/Boulder, CO (4,6,7,8)(on/off)  Help
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