Marine Weather and Tides
8/26/2020 The 7 day forecast is taking about 5 seconds to load but it will eventually load. NOAA is still working on it.
8/18/2020 NOAA continues to have trouble. Wind guest will occasionally be left off graphs. I am working with NOAA to resolve the issue.
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 7:13AM||Sunset 5:08PM||Thursday January 21, 2021 1:19 PM MST (20:19 UTC)||Moonrise 12:54PM||Moonset 1:51AM||Illumination 60%|
7 Day Forecast for Marine Location Near Foxfield, COHourly EDIT Help
Area Discussion for - Denver/Boulder, CO  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS65 KBOU 211757 AFDBOU
Area Forecast Discussion National Weather Service Denver/Boulder CO 1057 AM MST Thu Jan 21 2021
UPDATE. Issued at 1025 AM MST Thu Jan 21 2021
Based on webcams, some light snowfall seems to be ongoing along parts of the Continental Divide this morning. Shallow, limited moisture in WNW flow in the mountains will likely drive continued light snowfall through the day. The plains will remain dry. Temperatures are trending towards highs about 5 to 10 F cooler than yesterday on the plains, which matches forecast temperatures. The forecast is on track without changes this morning.
SHORT TERM. (Today and tonight) Issued at 345 AM MST Thu Jan 21 2021
There is some light snow falling over the divide and just to the east, mainly in Boulder and Larimer Counties at this time. Over the plains, many of the observations show the current wind field to be a mix of southwesterly downsloping and normal drainage patterns. Models have zonal flow aloft over the CWA today and tonight. The speeds at jet level are in the 70-80 knot range tonight. The QG Omega fields have benign synoptic scale energy for the CWA today and tonight. The low level wind and thickness fields show a weak cold front to get into the plains this morning/mid day. The low level winds will be upsloping through the day, with southeasterlies this evening before normal drainage patterns kick in by 06Z tonight. For moisture, cross sections continue to show shallow low level moisture in the mountains today and tonight. There is some mid an upper level moisture around here and there depending on the model. Current Satellite pictures show this to be reasonable. The QPF fields show limited measurable snowfall on all the models for the mountains today and tonight. Will keep the 30-60% pops going in those areas for the first two periods. Accumulations will be light. No pops for the plains. For temperatures, today's highs look to be 3-5 C cooler than Wednesday's highs.
LONG TERM. (Friday through Wednesday) Issued at 229 AM MST Thu Jan 21 2021
An upper level high will be parked over the eastern Pacific through the weekend and much of next week. Storm systems will dig south along the west coast of North America on the backside of the ridge. This will result in a wet active pattern for California. Most of these systems will drop into southern California before weakening and ejecting to the east/northeast across the Central and Southern Rockies. By the time these systems make it to Colorado, they will be weaker with limited precipitation.
On Friday two short wave troughs will be dropping south along the west coast. Over Colorado, weak ridging will track across the state. Could be enough moisture for light snow/flurries over the northern mountains, otherwise dry conditions are expected. Cross sections should a good amount of moisture and cloud cover. This will limit heating and keep highs near normal. One wave ejects east-northeast across the Great Basin and Central Rockies Friday night and Saturday. Expect light snow to fall in the northern mountains with this system. East of the mountains, the best chance for light snow will be over far northern Colorado. A surface low forms over southern Colorado Saturday and will pull cooler air in from the north. Some uncertainty when the cooler air moves in. Will it be early or late Saturday? This will determine the highs for Saturday. Sunday is expected to be quiet with the area in between systems. By late Sunday, the chance for snow returns to the mountains with the approach of the next system. Still some uncertainty on the track of this system. It could end up too far south for snowfall. The ECMWF is on the northern end of the models and brings light snowfall to most of northeast Colorado.
For Monday night through Wednesday, broad upper level troughiness is expected for the Central Rockies. Models are still trying to hammer out the specific details on strength, timing, and position of the upcoming systems. Weakening systems lifting northeast across the region is not a recipe for significant precipitation. The mountains should see light snowfall. For the Front Range and eastern plains, there will be a chance for light snow. Will have PoPs in the forecast for most of this time frame with the highest ones over the mountains. Temperatures should be near to slightly below normal under this pattern.
AVIATION. (For the 18Z TAFS through 18Z Friday afternoon) Issued at 1025 AM MST Thu Jan 21 2021
Expect VFR conditions at all terminals through the TAF period. Skies should remain scattered to broken in the mid to upper levels today and tonight. Winds should remain northwesterly at KDEN and KBJC through this afternoon, with intermittent gusts up to 25 kts at KBJC for much of that time. Expect easterly then southeasterly winds later this evening followed by drainage winds tonight and predominantly easterly winds tomorrow morning.
BOU WATCHES/WARNINGS/ADVISORIES. None.
UPDATE . Direnzo SHORT TERM . RJK LONG TERM . Meier AVIATION . Direnzo
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 - Centennial Airport, CO||6 mi||27 min||NNE 7||10.00 mi||Mostly Cloudy||48°F||16°F||28%||1013.6 hPa|
|Denver, Denver International Airport, CO||16 mi||27 min||E 14||10.00 mi||Mostly Cloudy||45°F||19°F||35%||1012.8 hPa|
Link to 5 minute data for KAPA
Wind History from APA (wind in knots)
|1 day ago||SE||E||NE||N||NW||W||Calm||S||Calm||SE||S||S||S|
|2 days ago||NE||N||NE||N||W||N||NE|
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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
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