Sunday, March 9th 2014
It's been an active start to the month of March for Colorado. Two wet storms have pushed Denver's snow totals for the season to just over 30 inches (still 16 inches shy of where they'll need to be by March 31 to end the month at average), but modest gains nonetheless. Both systems brought beneficial moisture to the region, though not all in the form of accumulating snow. Through the first week of March, Denver International Airport recorded 0.61 inches of precipitation, well above the normal value of 0.14 inches to start the month. Snowfall month-to-date is now at 3.5 inches. On average Denver sees about 11.5 inches of snow during the month of March.
We will be in between systems Sunday and Monday. This means a great deal of sunshine and warm temperatures along the Front Range. Pretty remarkably, the GFS MOS guidance has highs in the upper 70s Monday, guidance we haven't seen in some time. We think we'll be cooler than this in Denver, especially if mountain wave clouds kick in ahead of our next system due in Monday night. An increase in clouds Monday afternoon will keep our temps cooler than currently forecast -- but likely mild nonetheless.
Tue Temp Anomalies | GFS | WeatherBell
Another dramatic shift in the weather comes overnight Monday into Tuesday as our next system moves into the region. Highs Tuesday will be some 30 degrees colder than Monday with a chance for rain and snow returning to northeast Colorado.
This system does look colder than the last two and therefore we do expect mostly snow from this event. That being said, timing has the bulk of the precipitation falling during daylight hours Tuesday, and that in combination with modest QPF, we (at-this-time!) are expecting little accumulation at lower elevations. At this point the biggest wildcard we see as potential for heavier snowfall will, like our previous two systems, but enhanced snowfall Tuesday afternoon due to convection -- not yet being picked up too much by any of the models.
Tuesday's system is still offshore in the Pacific, which should always be pause for ruling anything out until it comes inland and we get a better sense for timing and track
. As it stands, however, both the GFS and EURO have similar ideas on how it progress across the west, before ejecting east and rapidly intensifying.
Notice on the GFS how it leaves behind a lot of energy as it passes over Colorado Tuesday. The surface low, while not all that strong at this point, then gets way out in front of the forward leading energy, and the impact across northeast Colorado (while cold) is minimal snow-wise.
East of Colorado the southern piece of energy joins forces with the northern branch, enhancing it and strengthening as it moves east.
GFS 72hrGFS 90hr
Then take a look at what the GFS has in mind for Wednesday into Thursday across the northeast. A 984mb low cranking east/southeast of New York with driving snow across New England clear through to West Virginia. The EURO looks very similar, though the track is even a bit further south than the GFS. The incredible winter for the east continues.
For the west, upper begins to take hold as this system moves east Wednesday. For now we are expecting a period of quieter weather across the west, with only a few little blips on the radar post Wednesday, but no significant storms at this time.
Thursday, March 6th 2014
If you saw the thick clouds over the Front Range today, then you've already noticed the first few signs that the weather is changing. Despite the warm temperatures, the clouds marked a change on the way.
These clouds are the leading line of the next winter storm. Right now over Utah and Idaho, the system has a good amount of Pacific moisture to push over Colorado to end the week.Friday morning drive to be easier easier than the afternoon
The storm will push over the greater metro area early Friday, lasting through the evening. There will be some minor impact to the morning commute, but a bigger impact to afternoon and evening drivers. The chance of rain and snow will increase by midday, remaining through the evening, and tapering off into Saturday morning.
Like the past couple of systems to visit the Front Range, you can expect a temperature drop with rain and snow -- and highs will be in the upper 30s and lower 40s.
Any snowfall accumulation is subject to rapid melting. Grassy areas in some locations will have a few inches by evening, and there will be some roads that have a slushy mess by the evening commute.
We expect the snow to continue into the early morning hours of Saturday. It's the snow during the overnight hours Friday that will have the best chance to accumulate. With slowly dropping temperatures, the change from rain and snow to all snow will likely happen in the afternoon, and the system will turn to all snow overnight Friday into Saturday morning.
The amount of snow we receive will depend on the time of day that the rain and snow changes over to only snow. This event is very determined by elevation. Assume a slightly earlier changeover and the ECM (first image) will likely pan out with some good totals for the western and southern Denver metro area in elevations above 5,500 ft. If the changeover occurs later, as in the RPM (second image), the accumulation will be less in Denver and higher for elevations above 8,000 ft.Skiers and riders will have new snow this weekend
The mountains will begin to see snowfall from the late this evening through the day Friday. Winter weather advisories in the central and western mountains call for 6 to 12 inches of snow by early Saturday morning. Travel will become more hazardous Friday through early Saturday.
Another impact will be the wind, especially in the high country, with gusts of 35 mph and higher. The wind may also increase for the foothills near the Front Range overnight as the system draws closer. This will create areas of blowing snow and reduced visibility.
We'll be tracking that changeover for you throughout the day Friday
, and keep you up to date with any further developments as this storm gets underway.
Sunshine returns quickly Saturday to melt off any snow that does stick!
Thursday, March 6th 2014
Soggy Friday | GFS | WeatherBell
The next system we've been tracking for well over a week now is due to arrive early Friday across northeast Colorado. Models continue to struggle with just how cold this system will be, but given a variety of factors, we estimate that tomorrow will see only a little snow, with most precipitation coming in the form of rain and a rain and snow mix.
The GFS has simply just been too warm for snow, with temperatures through the day Friday hovering at and above 40 degrees. The EURO, while colder, has similar issues. With the brunt of the precipitation expected during daylight hours, there is little reason to expect temperatures to cool more than models would suggest. And if the rain does change to snow, it will have a difficult time sticking during daylight hours.
The caveat here is timing. Should this system slow a little and allow more precipitation after sunset Friday, we'll need to watch for the possibility of a few locales getting better snow. Additionally, should any snowfall coincide with some possible convection Friday evening, a few places stand a chance for rapid (but short-lived) accumulation.
For now we will hold off on issuing any snowfall forecast for lower elevations (advisories are already out for points west). We're looking forward to what the next few rounds of modeling will try to do with this system as it nears.
In any case, you can expect Friday to be much colder across the region after highs near 70 degrees on Thursday in Denver. We'll keep tabs on this approaching storm, and offer updates as necessary. If need be, we'll fire up the Live Blog
tonight to track any changes to the going forecast.
Wednesday, March 5th 2014
Last night's snow was probably not as much as some would have hoped for, and likely more than others had hoped for, but it was a pretty good, quick-hitting system nonetheless.
Highs Tuesday peaked in the lower 60s across the metro area (64 degrees downtown, and 61 degrees officially at DIA). Within seven hours of those highs we had rain changing to heavy snow, bringing accumulating snowfall up and down the Front Range Tuesday night.
Totals ranged from about 1 to 6 inches, depending on when the rain changed to snow and how warm surfaces were at the onset. Central Denver received about 2 to 3 inches of snow. This was well within our forecast range (2 - 6" for DEN, with a BI of 7), but on the lower end for many. Important to note, that while these were the recorded totals, a lot of melting has already taken place -- almost as fast as it fell given the warm ground temperatures.
Today temperatures rebound nicely. We'll see highs in the mid 40s to near 50 degrees for most locales, with mostly sunny skies.
NWS spotter reports as of 7am March 5:
7.1" 4 miles NE Ward
4.8" Bergen Park
4.2" 1 mile SSE Evergreen
3.0" Federal Heights
2.5" Baker, Denver
Last night the snow fell hard at times. Here are a few clips (B-Roll!) from around Denver last night.