Marine Weather and Tides
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 6:08AM||Sunset 8:02PM||Tuesday August 11, 2020 12:18 PM MDT (18:18 UTC)||Moonrise 11:17PM||Moonset 12:46PM||Illumination 47%|
7 Day Forecast for Marine Location Near Sheridan, COHourly EDIT Help
Area Discussion for - Denver/Boulder, CO  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS65 KBOU 111646 AFDBOU
Area Forecast Discussion National Weather Service Denver/Boulder CO 1046 AM MDT Tue Aug 11 2020
UPDATE. Issued at 1046 AM MDT Tue Aug 11 2020
The forecast is on track given it's already in the mid to upper 80s across the Denver/Boulder metro area. Highs will reach the mid 90s, even upper 90s along the South Platte valley north and northeast of Denver. HRRR-smoke has captured the smoke/haze quite well for today. This evening the smoke should be confined to the northern quarter of Colorado before meandering south of east, covering just about every inch of our CWA in north Central and Northeast Colorado. Jackson, Grand, and Summit Counties will have the highest smoke concentration starting late this evening, particularly near the surface, but even along the I-25 corridor there will be a fair amount of smoke near the surface as well, especially by midnight and beyond.
In terms of convective chances today, surface observations and HRRR output continue to favor far eastern Colorado where surface dewpoints are in the 50s and a dry line should sharpen by 1 PM from Sterling to Akron to near Limon. Convection forms first along the Palmer Divide around 1 PM, then may build northeast along the dryline into Washington County by 3 PM. Still a marginal risk of severe storms for Washington, Lincoln, eastern Logan, Phillips, and Sedgwick Counties through about 4 PM. After that, very little convection is expected across our area.
SHORT TERM. (Today and tonight) Issued at 250 AM MDT Tue Aug 11 2020
After a brief break on Monday, temperatures are again expected to bounce back in the 90s across the urban corridor and northeast plains this afternoon. A weak west/southwesterly flow aloft will be over the forecast area with a broad ridge of high pressure stretched across the southern U.S. Skies will again be hazy as wildfires on the west slope continue to spread smoke in the forecast area. A weak upper level disturbance is still progged brush across northern CO around 00z. The airmass will be quite dry however from the urban corridor westward into the mountains. Consequently, just a few weak high based showers/thunderstorms will be possible. Brief pulse type storms will produce gusty winds but little if any rainfall. A dry line will set up east of Denver this afternoon. Better moisture east of this line with sufficient CAPE to produce one or two severe thunderstorms. The northeast plains are under a marginal risk this afternoon, with the best chance of severe east of a line from Sterling to Akron to Limon. Latest HRRR and RAP models show limited development, with the strongest storms east of this line after 4 pm. The HRRR does suggest one or two storm could produce wind gusts to 60 mph. Most of the thunderstorms activity will diminish by 9 or 10 pm. Clearing skies over night, with some patchy stratus possibly developing over the northeast plains after midnight.
LONG TERM. (Wednesday through Monday) Issued at 250 AM MDT Tue Aug 11 2020
Upper level high will remain over the Southern Rockies through most of the week. This will result in a very warm and dry westerly flow aloft. Temperatures over northeast Colorado will be in the mid to upper 90s through Friday. Could see isolated convection over the mountains. Gusty winds and little to no rainfall will accompany this convection. Enough low level moisture could creep into the far northeast corner of Colorado for thunderstorms Wednesday, otherwise the lower elevations look dry through at least Friday.
The upper level high starts to shift westward Friday and by Saturday it will be located over the Desert Southwest. Flow aloft will turn northwesterly. Temperatures may drop a few degrees Saturday due to a weak cold front, but lower 90s are still expected for northeast Colorado. This may usher in just enough moisture for isolated showers and thunderstorms, thus will have some low PoPs in the forecast. A short wave trough rounding the top of the ridge and a cold front is expected Saturday night. High temperatures will cool into the 80s behind the front for Sunday. Low level moisture should also increase bringing a chance for showers and thunderstorms. The airmass warms some Monday with highs approaching 90 degrees over northeast Colorado. If southeast winds over eastern Colorado prevail, this will help retain low level moisture. Will have low PoPs for Monday as well.
AVIATION. (For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1046 AM MDT Tue Aug 11 2020
VFR conditions through Wednesday. SW winds should go more west this afternoon, around 10-15 kts. No convection is expected near the terminals, though a line of strong thunderstorms is possible across northeast Colorado between 1-4 PM. Winds tonight will return to drainage around 10 kts (SSW DEN and APA, W at BJC). On Wednesday, hot again with no chance of precipitation. Winds should again be out of the west during the afternoon hours at around 10 kts.
FIRE WEATHER. Issued at 250 AM MDT Tue Aug 11 2020
No fire weather highlights today although the fire danger will remain high. The dry conditions and above normal temperatures will be offset by lighter winds and limited thunderstorm coverage.
Very warm and dry conditions will remain over the Central Rockies through Friday. Relative humidity recoveries will be very poor along slopes and ridges with readings less than 40 percent. Relative humidities will bottom out at 8-18 percent during the afternoons. Breezy conditions are expected to occur with afternoon gusts of 15- 25mph. Slight cooling and higher humidities are expected for the weekend. However, this slight improvement is expected for the Front Range mountains and eastward with little to no improvement for the western and central Colorado mountains.
BOU WATCHES/WARNINGS/ADVISORIES. None.
UPDATE . Schlatter SHORT TERM . Cooper LONG TERM . Meier AVIATION . Schlatter FIRE WEATHER . Cooper/Meier
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||14 mi||26 min||Var 4||10.00 mi||Mostly Cloudy||89°F||25°F||10%||1009.7 hPa|
|Broomfield / Jeffco, CO||16 mi||32 min||S 6||10.00 mi||Mostly Cloudy with Haze||90°F||37°F||16%||1018.6 hPa|
|Buckley Air Force Base Airport, CO||17 mi||21 min||N 0||10.00 mi||Partly Cloudy||91°F||26°F||10%||1009.5 hPa|
|Erie Municipal Airport, CO||23 mi||25 min||SSE 7||10.00 mi||Fair||90°F||30°F||12%||1016.9 hPa|
|Denver, Denver International Airport, CO||24 mi||26 min||SSW 7||9.00 mi||Partly Cloudy||93°F||30°F||11%||1007.7 hPa|
Link to 5 minute data for KAPA
Wind History from APA (wind in knots)
|1 day ago||NW||N||Calm||Calm||E||S||S||E||SW||SE|
|2 days ago|
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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 (14,3,4,5)(on/off)  Help
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