wxgeek's weather-Dry/mild week, Snow nxt friday-Update 11/5

Update Mon Nov 5

Another very nice day across the state today. Don't get me wrong, I'm all for nice weather, but our state could really use some moisture. Looks like we will have to wait for the weekend for that. Dominant upper ridge centered over CA currently, which is creating some decent Santa Ana winds over SoCal, will migrate east during the week. As the ridge passes over CO mid week, temps will be well above seasonal norms. Then a large upper trough will move into the West Coast by late week, bringing rain and snow to the West Coast. We will see northerly flow aloft early in the week, replaced by southwest flow aloft as the upper trough approaches CO on Friday. As southwest flow aloft increases, surface winds of 15-35 mph will become likely Friday across CO, which could prompt some red flag warnings as conditions are quite dry across most areas of the state. Precip will move into western CO during the day on Friday, spreading east as cold front moves through CO Friday night. Models continue to suggest the upper trough will split into a northern and southern branch, with the majority of energy with the northern branch. Significant snowstorm looks to be on track for MT, WY, ND and SD late this week into the weekend. For CO, majority of precip will remain west of the Divide as upslope component to this system looks weak at best, to non-existent east of the Divide. Perhaps a brief period of upslope after front passes Friday night into Saturday morning, which is likely the best chance for accumulating snow for the foothills and Plains. Models still pretty stingy with moisture east of the Divide, so perhaps 1-3 inches of snow in more favored areas Friday night through Sunday morning, and a dusting to an inch in less favored areas. Mountains could see 2-6 inches with this system, with highest amounts north of I-70. Models still offering slightly different solutions with each run, so the forecast could change some between now and Friday. Temps will definitely be cooler after the front passes Friday night, with temps well below seasonal norms this weekend.

For next week, models still indicating additional chances for precip mid to late next week. For those interested in a winter outlook for CO, Mike Baker from the NWS office in Boulder provides a nice powerpoint presentation at http://www.crh.noaa.gov/images/bou/show ... -Baker.pdf

In general, the building El Nino conditions in the Pacific have waned, so it looks like we will see neutral ENSO conditions, with a possibility of weak El Nino conditions the remainder of the snow season. This translates to near to slightly below normal precipitation for most areas of CO, with above normal temps expected. The potential for big snowstorms will exist, just not as likely if a more intense El Nino was present. The good news is that strong downslope wind events will be less likely under either scenario, as these are most prevalent during more intense La Nina episodes.

I really feel for the people still without power on the East Coast. Nature will show no mercy this week as a strong winter storm will pound the mid-Atlantic and New England area Wednesday and Thursday, An additional inch of rain will be common, accompanied by 20-50 mph onshore winds and high waves. Snow will remain 100-200 miles inland, with rain along the coastal areas, but temps will be in the upper 30's to low 40's in coastal regions. An interesting explanation of superstorm Sandy from Bob Henson of UCAR is available at the following link for those interested: http://www2.ucar.edu/atmosnews/opinion/ ... tion-sandy

So, from a weather perspective, a good day to get out and vote Tuesday if you have not already done so. It will likely be a lively and interesting day to watch our democratic process in action.
_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

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More dry and mild weather is expected this coming week across CO. Upper ridge will build along the West Coast and migrate into the Great Basin mid week. Upper trough finally moves along the West Coast late this week, which will bring cooler weather and a chance for snow to CO by Friday and extend into the weekend. Models have been suggesting that the upper trough will split, with the majority of energy staying north into the northern Rockies and northern Plains, with the southern portion remaining through the central Rockies over the weekend. The result looks to be a significant snowstorm for the northern Rockies and Plains, while CO receives light amounts of snow. We never get a deep upslope flow, so areas west of the Divide will receive more snow, while the foothills and Plains receive light amounts. Currently looks like snow moves into western CO during the day on Friday with snow level 6500-7500 ft during the day. As cold front and surface low move east by Friday night, foothills and adjacent Plains may get some snow Friday night into Saturday, with some flurries lingering into Saturday night and Sunday, but any accumulation east of the Divide looks quite light. Major snowstorm for MT and the upper Plains. Long range models suggest a better chance for snow the following week across CO, especially the foothills. Time will tell if this system could become a significant snow event for us the following week, Wednesday and Thursday.

For election day, most areas across the country will have pleasant weather for voters. Some rain showers possible across FL and the southeast, while some light snow is possible across the western Great Lakes, and some rain in WA. Overall, a nice election day weather wise. Another significant winter storm will form off the NC coast on Tuesday night and move north just off NJ/NY on Wednesday, then move into New England Thursday. This system will bring more rain, easterly winds and waves to the mid Atlantic states on Wednesday, exacerbating the already bad situation left over from superstorm Sandy last week. Areas could receive another big ocean surge with weakened shores, and strong winds could impact trees and power lines left vulnerable from Sandy.
_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

Bump for Nov 5 update