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 6:39AM||Sunset 7:27PM||Thursday April 2, 2020 4:30 AM MDT (10:30 UTC)||Moonrise 1:04PM||Moonset 3:29AM||Illumination 69%|
7 Day Forecast for Marine Location Near Nunn, COHourly EDIT Help
Area Discussion for - Denver/Boulder, CO  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS65 KBOU 021016 AFDBOU
Area Forecast Discussion National Weather Service Denver/Boulder CO 416 AM MDT Thu Apr 2 2020
SHORT TERM. (Today and tonight) Issued at 415 AM MDT Thu Apr 2 2020
An upper trough over the northern Great Basin and Northern Rockies will be dropping south today, while high surface pressure to the lee of the Rockies pushes very cold air south across the Colorado plains. The main cold front of the system is pushing into northwest Colorado this morning, which will be ramping up snowfall rates over the northern mountains, coinciding with our Winter Weather Advisory start time. Through the morning and into the afternoon, the mountains may see snowfall rates around 1 inch per hour. Overall, still expecting 4 to 8 inches over the high mountains, mainly north of I70, with some isolated areas of up to a foot. Across the plains, last nights cold front has created a cold and moist airmass with areas of fog and drizzle. Much colder temperatures near the Wyoming border has allowed for freezing drizzle, which should mainly stay far north of I-70. A surface low over the central mountains may allow for some southerly winds to push back in over the Palmer Divide and southern Lincoln County for a brief warm up today, otherwise max temperatures will be in the 20s to 30s across most of the area.
A 700 mb cold front will push down across the mountains this morning, then across the plains this afternoon. The areas of drizzle should quickly change over the snow with colder air and moisture increasing. The upper jet will be sinking over the forecast area to help produce banded snow. Models have been converging on a SW to NE oriented band setting up this afternoon into the evening starting around the Palmer Divide area and up into the northeastern plains. At the same time, the strong cold advection and surface gradient will create strong northerly winds, with gusts up to 45 mph possible. There is some potential for the need of a highlight for this area, however the timing of the worst conditions should be relatively short and the exact location of this band is hard to pinpoint. Overall, snowfall amounts in this area will be 2 to 4 inches, where the rest of the plains will likely see a trace to 2 inches.
Subsidence on the backside of the trough will end snow over the area overnight, with some clearing in the skies. Therefore, overnight lows will be very cold for early April, and will likely see some areas of fog forming, especially over the South Platte River Valley.
LONG TERM. (Friday through Wednesday) Issued at 415 AM MDT Thu Apr 2 2020
Friday will start off quite cold. There may be some patchy fog if skies clear sufficiently, with the most likely area of fog in eastern Larimer and Weld counties where T/Td spreads will be small. There appears to be enough dry low level air, in combination with southeast flow off the Palmer Divide, to reduce the stratus deck. That should allow for modest daytime heating before convective temps are reached and shallow cumulus/ stratocumulus fills back in. Best chance of getting light showers will be in/near the Front Range Mountains and Foothills with low level convergence and elevated heat source, but even those showers could be challenged to get going considering the strength of the cap. Highs will only reach the lower to mid 40s across most of the area, with 30s in the mountains and foothills.
For Friday night, there is potential for a weak upper level disturbance to graze the forecast area. We think models are overdoing the amount of moisture, but we'll keep just a slight chance of showers in the forecast for the high country into Saturday. Temperatures will warm Saturday (close to normal) with more sunshine and downslope flow just off the deck.
The warming trend and generally dry weather will continue through Sunday under southwest flow aloft. The addition of lee troughing will bring an increased downslope component. Thus, highs should be able to reach the 70 degree mark on most of the plains for Sunday and Monday. There is reasonable agreement in this forecast. A weak ejecting short wave Sunday could bring an isolated storm or two to the high country.
We don't see much change in the weather pattern through Tuesday as Colorado will be in between a cutoff low dropping off the coast of California and the northern branch of energy riding along/just north of the Canada/U.S. border. There should be a little cooling by Wednesday as backdoor cold front may slide across the plains. Showers will eventually return to the forecast by late Wednesday or more likely Thursday as the cutoff low off the California coast may finally eject this way.
AVIATION. (For the 12Z TAFS through 12Z Friday morning) Issued at 415 AM MDT Thu Apr 2 2020
Low level clouds, areas of drizzle and fog will continue early this morning. IFR conditions will likely remain throughout the day, with some LIFR due to fog early this morning. Another cold front will push south across the area to bring snow after 3 PM at the metro area terminals, but accumulations on concrete surfaces should light if anything at all. Winds will remain east or northeast throughout the day, with gusts to 25 kts this afternoon with the front. Snow will diminish and skies to clear after midnight to allow for areas of fog to form, but this should remain near and along the South Platte River Valley.
BOU WATCHES/WARNINGS/ADVISORIES. Winter Weather Advisory from 6 AM this morning to midnight MDT tonight for COZ031-033.
SHORT TERM . Kriederman LONG TERM . Barjenbruch 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.
|Fort Collins/Loveland - Northern Colorado Regional Airport, CO||16 mi||34 min||E 10||6.00 mi||Light Snow Fog/Mist||29°F||27°F||92%||1006.8 hPa|
|Greeley, Greeley-Weld County Airport, CO||21 mi||34 min||NE 9||10.00 mi||Overcast||28°F||26°F||92%||1009 hPa|
Link to 5 minute data for KFNL
Wind History from FNL (wind in knots)
|1 day ago||N||Calm||S||Calm||NE||SE||SW||W|
|2 days ago||N||N||SE||NW||N||N|
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GEOS Local Image of CentralPlains 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 (6,6,7,8)(on/off)  Help
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