Dense Fog Advisory issued October 21 at 2:30AM MDT expiring October 21 at 10:00AM MDT in effect for: Cheyenne
The hurricane force winds that battered the Front Range early Tuesday were brought to us by a one-two combination of strong jetstream winds aloft and a fast moving cold front at the surface. Some of the winds reached speeds of over 100 mph in Larimer and Boulder counties Tuesday morning. By late in the day, the jetstream winds had weakened and the cold front had pushed to the east of Colorado, bringing the fierce winds to a halt.Most of the last day of 2008 will be mild, dry and quiet over Colorado, but more strong winds are likely tonight and for New Years Day. To the west, another impulse of jetstream winds is building and heading our way from the Pacific Northwest. Yet another surface cold front is also moving in as well. Winds will be increase over the northern mountains and foothills late today and continue strong through Thursday morning. This next system does not appear to be quite as strong as the previous one, but winds may still reach 50-70 mph tonight over the same areas that were blasted by wind on Tuesday.By Thursday afternoon, the winds will lessen and the weather should be rather quiet and pleasant for Friday and Saturday. On Sunday, some colder weather and a little light snow will return to the forecast. Looking ahead over the next 7-10 days, it now appears that the really cold air will stay bottled up in Alaska and western Canada for a while. Colorado will be slightly cool for the first week of the new year, with some periodic light to moderate snows in the mountains. Lower elevations will stay mainly dry, with temperatures averaging a little colder than normal. Westerly winds rocketed down from the Continental Divide overnight with the foothills locations of Larimer, Boulder and Jefferson Counties bearing the brunt. The combination of an approaching cold front and a powerful jetstream moving in from the west has brought very strong winds to the Front Range. The cold front will push east of the state by this afternoon and the winds aloft will weaken, giving wind weary residents a break.Some of the gusts reported have been pretty amazing - * 98 mph - Berthoud ( 7 miles northwest ) * 91 mph - Carter Lake * 86 mph - Longmont ( 2 miles north ) * 76 mph - Broomfield ( 2 miles southwest ) * 71 mph - Erie ( 1 mile southwest ) * 69 mph - Boulder ( 2 miles southwest )Strong winds will continue through Tuesday morning and then gradually subside in the afternoon. The weather will cool off for New Years Eve and New Years Day, with highs in the 30s to mid 40s and no major storms. Into the first weekend of 2009, there are no major snowmakers coming into the region.I am watching a new pool of very cold air that is developing in Alaska and northern Canada. Temperatures in the interior of Alaska are running 20 to 35 degrees belwo zero. It now appears that the icy air will slide southward and head toward Colorado early next week. Stay tuned, I will keep you up to date, but be prepared for another cold outbreak by Jaunary 6th or 7th. Another storm system has brought heavy snow to the mountains. WINTER STORM WARNINGS cover most of the high country along and west of the Divide through Friday. Additional snowfall should be in the 8-16 inch range west of the Divide and in the 4-8 inch range farther east.In Denver and across the eastern plains, we can expect cooler temperatures with a few snow flurries. A cold front will slide into the state from the west and bring some chilly northwest winds and light snow of flurries. Most snowfall totals will only be in the 1/2 inch range, but the gusty winds and colder weather will make it feel more like late December.After this most recent storm exits the state. it currently looks as though drier weather will move in for the last few days of 2008, with only a little light snow in the mountains and little, if any on the plains. Temperatures should rally into the upper 40s in the Denver area on Sunday, and perhaps into the 50s on Monday! It almost feels like Spring given what we've come from in terms of temperatures, but more cold is forecasted to make its way into the region again this weekend. It took most of the fall, but we are finally in a pattern where snow and cold is affecting us as opposed to the dry, mild conditions we experienced through October and November.This weekend's cold snap doesn't look as bad as what we saw this last weekend, so right now we are not expecting readings in the teens below 0, nor are we expecting as much snow. Right now, it looks as if Saturday and Sunday night will be the coldest with overnight lows at or just slightly below 0 and highs in the teens. There is a chance for some light snow, but there won't be a lot. Different story in the mountains as they may get another round of heavy snows, but they won't make it down to lower elevations.Looking ahead to Christmas, it looks as if the pattern will return to a more quiet and mild setup, and thus we are looking at a Christmas with above average temperatures and little to no chance for snow. The bitter cold airmass that settled into eastern Colorado over the weekend is slowly loosening it's icy grip, but we have a long ways to go. Record cold has remained frozen in place for three consecutive days in the Denver area. Minus 18, -19 and -8 degree readings Sunday, Monday and today have all broken or tied records for Denver, the minus eight matching a mark last set 111 years ago!The cold air has been too dry to support much moisture, so snowfall has been very light, if any on the eastenr plains. Such is not the case in the high country, where snow continues to fall, heaviest over the San Juan Mountains. The mountains have been more influenced by a strong jetstream flow that is helping bring moisture from the Pacific. The heaviest snows have been in Silverton, Wolf Creek and surrounding areas. Some parts of the southwest mountains have received over three feet of snow since Saturday, with more on the way.The deep freeze should ease a bit across eastern Colorado this week, with a slow warming trend expected for the next few days. The mountains will still get more snow. Our next chance for snow in Denver will be flurries on Thursday and more snow and cold by the weekend. The arctic cold front arrived on schedule Saturday night, bringing bitter cold air and a few inches of snow to the plains. Temperatures have taken a nosedive over eastern Colorado with readings dropping 60 degrees from Saturday afternoon. The cold front sliced southward late Saturday, pouring icy air down from central Canada all the way to the southern plains of the United States. Some of the worst weather was in the Dakotas, where extreme blizzard conditions were reported. Temperatures in North and South Dakota ranged from zero to 10 below, with north winds gusting to 50 mph and visibility limited to a few hundred feet in heavy snow. For much of Saturday night and Sunday morning, the western half of North Dakota was under a "Civil Emergency" - law enforcement strongly urging everyone to stay inside their homes due to the life threatening weather.In Colorado, the cold and snow caused very poor driving conditions over the mountain passes and along I-25, especially north of Denver. Roads were also very slick across the northeast plains. The snowfall on the plains has mostly been in the 3-5 inch range, with the dry, fluffy flakes fluttering down into the afternoon. The mountains received much more snow, many of the ski resorts reported one to two feet of snow in the past 36 hours. All of the Colorado mountains now are classified as HIGH DANGER for avalanches - according to the Colorado Avalanche Information Center. To see more information about the ski areas and avalanche conditions, check our SKI REPORT feature at the top of the weather navigation bar.The cold weather will stick around for several days as a large arctic high pressure system will remain anchored over the Dakotas and help keep the floodgates open for the frigid air. Our CURRENT WEATHER button on the nav bar will enable you to quickly click and see the current temperatures from the Denver area, all the way to Alaska!There will be periods of snow coming our way as well this week. A strong jetstream flow will continue to blow above the central Rockies and this fast flow aloft will swing more energy into the atmosphere late Sunday and Monday. The snow has lightened up in the mountains, but it is expected to intensify again Monday. The overall weather pattern this week will likely result in another one to two feet of snow for the mountains. Here we "snow" again! A strong storm system is moving south from the Gulf of Alaska and will race into the northern plains tonight and Saturday. This storm will arrive in Colorado late tomorrow with colder temperatures and a good chance for snow. The exact track of the storm is still uncertain, but it does appear that significant snowfall can be expected for the mountains, with a chance for several inches of snow at lower elevations as well.This arctic cold front will impact much of the western United States. Winter Storm Watches are in effect for western Colorado, Utah and most of the northern Rockies. The combination of the cold front and a strong upper level jetstream will help to create a snowmaking machine for the high country, with 2 to 3 feet of snow likely in the mountains! Denver and the eastern plains will experience much colder weather, and much lighter snowfall, with about 3-6 inches of dry, fluffy snow expected Saturday night and Sunday.We have developed an outstanding ski report feature - check it out on the top of the weather navigation bar! Stay tuned to 7News and TheDenverChannel.com for more information on this upcoming storm. The most recent storm system to hit Colorado came in fast and cold late Monday, with strong north winds and moderate to heavy snow over the I-25 Corridor. Most snow totals in the Denver Metro area were in the 4 to 8 inch range, but some foothill locations had closer to 10 inches of snow.The snow also hit over the mountains, with heavy snows of at least a foot across the San Juan and Sange de Cristo Mountains. In Summit County and vicinity, skiers and snowboarders will enjoy a powder day, with 5 to 10 inches of snow. The driving may pose a problem early, but conditions should improve by midday.The weather will not improve in the Midwest as this storm will dump plenty of precipitation from the Gulf of Mexico to the Great Lakes. Strong thunderstorms will be likely over the lower Mississippi Valley, with sleet and snow in the Ohio Valley and heavy snow in the Great Lakes. If you have travel plans today, check our TRAVEL WEATHER button on the navigation bar.The weather will be cool and quiet for several days, but we will be watching a potential storm for the weekend and early next week. This system will spin in from the Pacific late Sunday and could be a heavy snowmaker for Colorado. That storm is still a long way off, so stay tuned to 7News and TheDenverChannel.com for the latest. The wild roller coaster ride continues in the weather department as another big change is upon us today and tonight. After a delightful day on Sunday, with highs in the mid 60s, a strong cold front will slice through the area this afternoon, bringing cold north winds and more snow. We actually will be affected by two storm systems in the next 24 hours - the cold front, coming down from Wyoming and a low pressure system spinning into southern Colorado from Arizona.The cold front will play the biggest role in the weather for Denver and vicinity. This front will bring a blast of colder air and snow to the region this afternoon and tonight. The heaviest snow will occur on the south and southwest sides of Denver, with up to 6 inches possible in Douglas and Jefferson counties. In the downtown Denver area, up to 3 inches of snow may accumulate by 9 AM on Tuesday. Farther norht, snow totals will be in the 1 to 3 inch range. In the foothills west of Denver, 4 to 8 inches of snow will likely fall. The Monday afternoon drive will not have much snow to worry about, but Tuesday morning will be sloppy, slushy and slower.Southern Colorado will feel the impact of the southern storm, there is a WINTER STORM WARNING in effect for the Sangre de Cristo Mountains, where over a foot of snow is expected. Most of the rest of the Colorado high country can look forward to a fresh cover of 5-10 inches of snow through Tuesday morning.The storms will quickly exit the state on Tuesday, with clearing skies. The middle of the week will be dry and milder with sunshine and temperatures getting back into the 40s to low 50s. By the weekend, we are watching a potential storm that will likely come in the form of a strong Canadian cold front, bringing more snow and chilly temperatures to the entire state. After an early winter blast that dumped 3-6" of snow on the Front Range, the weather will turn drier for the end of the week. Overnight, the clearing skies allowed temperatures to drop into the single digits. Some dense fog also developed in the Denver Metro Area. Today won't be quite as cold with mostly sunny skies and highs in the low 40s. Looking ahead to the weekend, Broncos Sunday will be great with mostly clear skies and highs in the upper 50s. Monday will bring another slight chance for snow as a cold front moves across the state.The middle part of the week looks calm with mostly sunny skies. Highs will range from the mid 40s to the mid 50s. We're keeping an eye on the long range models though, which show a potential for some heavier snow by next weekend. This scenario is still a long way out, so we'll have more details by next week. The weather will remain very cold today, with periods of snow expected over the northern half of the state. In Denver and the surrounding area, we can expect 2-4 inches of dry, fluffy snow to accumulate throughout the day. The cold airmass that has settled into the area will keep temperatures hovering around the 20 degree mark for today.In the mountains, the snow will be heaviest along and north of I-70, with 6-12 inches of snow likely before the storm winds down tonight. The southwest mountains will miss out on this storm, with only a couple of inches of snow possible.Skies will clear tonight as the storm system moves out. With the fresh snow and the clearing skies, we can expect a very cold night. Low temperatures will tumble to the single digits by morning in the Denver area, with subzero readings in the mountains.Sunshine will return for Friday and the weekend and warmer temperatures will result. In fact, by Sunday the temperatures may bounce all the way back to the 60 degree mark in Denver - very nice for the Bronco game. The next front will arrive Monday, with a chance for light snow and colder temperatures. The fast paced weather pattern that has kept Colorado on a meteorological roller coaster will bring a dose of cold and snow today. After an unseasonaly warm Tuesday with highs near 70 degrees, a strong cold front has blown through the state, bringing a 35-40 degree drop in temperatures and another round of light snow. The snow will gently fall off and on through Thursday in the metro area and may total up to 2-4 inches before it ends. Northern extremes of the state could see double that total, while the mountains around Steamboat may end up with nearly a foot of snow.The brunt of this storm system will affect the northern half of Colorado, while the south and southwest parts of the state will miss the majority of the cold and snow. If you are planning to travel during the next 24 hours, the worst driving conditions should be on I-80 in Wyoming, I-76 into Nebraska and I-25 north of Denver. Interstate 70 will have icy and snow covered areas from west of Evergreen to about Gypsum. Highway 40 will be snowpacked and slick over Berthoud and Rabbit Ears.The storm will exit the state early Friday, with clearing skies and milder weather for the weekend. The next cold front will arrive Monday, with a chance for more snow in the mountains. Right now, it does not look as though it will be a major storm. If you're a sky watcher, you'll love the scene in the southwestern sky! The planets of Jupiter and Venus are visible along side the crescent moon. The best viewing will be about an hour after sunset and looking southwest. Try to get away form the city lights and you'll have a much better view of scenic nighttime sky.Meanwhile, areas of Colorado are recovering from the surprise snowstorm that rolled through over the weekend! Predictions for the weekend were generally much lighter than what we actually saw. What happened was something called "convective symmetric instability", or CSI. What happens is a summertime-like instability profile sets up creating a thunderstorm-like environment. When this happens during the winter, we typically see bands of very heavy snow form in areas as isolated as those in a summertime thunderstorm pattern. When combined with the weak upslope that was suppose to lead to the lighter accumulations we called for, this CSI element adds two or three times that amount. Unfortunately such events are not seen in the models, and in this case, there was not any real instability forecasted, thus we had no real advanced warning on such an event. That lead to the lighter than reality predictions we saw, and thus fooled most of us in the weather-forecasting arena from the National Weather Service all the way over to us here in the 24/7 Weather Center. While its no excuse, I hope this helps explain a bit about what happened over the weekend!