Monday, December 22nd 2014
Okay you procrastinating Santas, still looking for that perfect gift for your perfect weather geek at home? We’ve got a few ideas we’ve been cooking on for awhile, we’ve just been sidetracked tracking all those snow (err… rain) storms of late. Whether you’re dashing through the snow over the next few days, or splashing through the rain, this shopping list will make a weather geek’s dream come true.
Top 10 gifts for your favorite meteorologist (in no particular order)
10. Cloud Lamp. Admittedly not the most affordable item on our list, but too cool not to share. If it’s outside this year’s budget, no worries you can see it in action here.
9. Vantage View. One of many weather stations available for amature weather enthusiasts. This station runs the middle of the road pricing for weather stations, and gets you all the goods from current temperature, to precipitation totals and rate, wind speed and direction, to pressure and humidity and more.
8. Weather Stone. If you’re looking for something a little more affordable, but still incredibly accurate (with real-time weather reports at least), look no further.
7. RadarScope. On the digital side here’s one of our favorite applications for tracking weather both locally and nationally. RadarScope costs $10, with additional upgrades (real-time lightning) available. RadarScope is available in both the App Store and Android store.
6. Aeroweather. A very cool app for tracking current weather conditions at airports around the world. Aeroweather is available both for free and for an upgraded ‘pro’ version.
5. Handheld Anemometer/Thermometer. Great stocking stuffers here! These will run you anywhere from $20 to $100 depending on what bells and whistles you want included.
4. Galileo Thermometer, Glass barometer. Matt loves his. Colored water fills the thin glass barometer, and the level of the water in the spout goes up and down based on the atmospheric pressure. He added it to all his ship’s barometers/thermometers….although he needs to refill it now that he's settled into a new house.
3. Admiral Fitzroy Storm Glass. This is really a cool desk topper. Crystals form in the glass based on the pressure, giving a “prediction” of incoming weather.
2. Antique Tornado Siren Radio. A lot of antique stores have very interesting weather things. From old manuals and books, to the almost unknown items. In Matt's collection is an old “tornado siren radio”. Clearly the idea didn’t work, but a cool shelf item too. A true weather nerd will like anything old.
1. CoCoRaHS Official Rain Gauge. If you’re not a part of CoCoRaHS, you should join! CoCoRaHS is a collaborative rain snow and hail reporting network, and to join you’ll want to make sure you have a good rain and snow gauge before joining.
Bonus! A Weather5280 shirt! (we have a few around, email us at Weather5280@gmail.com).
Have some favorites of your own? Add them in the comments below!
Sunday, December 21st 2014
Heavy mountain snow
As we posted last night, big time snow is falling in the Colorado high country this evening. Some resorts are already reporting 5 - 10” of snow today, with more on the way through Monday. If you’re planning to ride some of the fresh powder over the coming days, visit FreshyMap for all the latest ski conditions across the state.
Here’s an awesome look at Breckenridge this evening (16” so far just south of town), with additional 10”+ possible through Monday. If your travel plans take you west through the high country, it’s best to wait until later in the day Monday if you can, and check with CDOT before doing so.
Across the plains we’ve seen plenty of clouds and a few showers this afternoon. We continue to think a few locations will see some snow over the next 24 hours, but this won’t be a widespread event. Downslope winds will be tough to overcome for communities west of I-25 at lower elevations, with those east of the interstate seeing a better chance for these bands of rain and snow.
The big question is where these bands will be able to form in and around the Denver metro area. Latest models indicate the best chance for snowfall accumulation through Monday will be south and southeast of Denver proper, with 1 - 3” possible under heavier snow bands. Latest SREF means keep snowfall at DIA at less than an inch, with 1 - 2” over southeast Aurora, Parker and along the Palmer Divide. Again -- these snowfall totals are for areas that see these narrow snowfall bands, not widespread totals. Most locations across lower elevations will see little or no snowfall with this system.
While we’re already seeing some banding take place up near the Wyoming border we’ll need to keep an eye on things closer to Denver as we head into the overnight hours. Satellite not all that impressive at this time, so not banking too much hope on snow in the city. We’ll see.
The SREF has a chance of snow in these areas for tonight and Monday.
However, that’s just a look at snow. Here’s a look at SREF probabilities for at least 1 inch of accumulating snowfall tonight and Monday.
Temperatures Monday will be cooler than what we saw across lower elevations today as our storm system pushes east. With those cooler temperatures will be an increase in winds at lower elevations. The National Weather Service has already issued a High Wind Watch for extreme eastern Colorado for Tuesday, with winds on the increase overnight Monday.
We dry things out Tuesday, and warm things up a bit too as we head into Wednesday.
Saturday, December 20th 2014
Remember the opening sentence in Thursday night’s post: “A lot of folks jumping on the White Christmas bandwagon today, so I’ll begin this post with a word of caution”. This was inspired by a local TV station posting one model’s operational run snowfall forecast over eight days, leading many to believe there’d be a foot or more of snow on the ground by Christmas in Denver. Other media outlets followed the lead by promising a Christmas snow…really?! Did no one look at the models? Today, just two days after those forecasts, that same model that started the craze has cut its forecast snow totals by 84% through Thursday. It’s time that media outlets start analyzing the models and their ensembles, looking for the hows and whys, to prevent eating crow.
As the season snows, snow goes the snow?
We have a lot of moisture coming in over the western third of the country. Rain and snow cover much of California, Oregon, Washington, Idaho, Nevada, Utah, Wyoming and Montana. This moisture is now moving into Colorado for tonight night, Sunday, and Monday.
GFS 6 precip shows heavy mountain snow Sunday night
The direction of this "flow" is from the northwest, which is generally not a good direction for anyone east of the mountains to get snow and or rain. However, the central mountains to the western slope will have lots of moisture Sunday and Monday. Some will have feet of snowfall. Many of the resorts will be adding well over a foot of new powder in time for the holiday rush of skiers/riders. Those resorts that face west and north will come out ahead of the others.
It may surprise you that very little of all that moisture is going to get on the eastern half of the state, including the Denver area, although the entire state will see the clouds. A cloudy sky expected tonight through Monday for the metro areas. Denver and the Front Range has a slight chance for snow/rain by Sunday night and Monday. During this period, a stronger wind will be blowing overhead, 20,000 feet or so, and that may draw enough energy to give a snow band or two for the city areas. That is only If that wind can tear enough moisture away from the mountains, like pulling strands from a cotton ball.
While a few days ago it looked a bit more promising that we’d have enough energy to enhance a few of these snow bands, at this time this does not appear to be the case. In cases where some banding may occur, the troughs will be to the east of us, thus limiting the lift and limiting the extent and amount. A weak cold front Monday will not do too much to shift our winds and enhance upslope either. If we manage to ‘steal’ some moisture from the mountains, the result will be a few areas with a few inches of snow, but not for everyone -- just in small pockets.
This first push of moisture will take a bit of a break Tuesday and Wednesday, which will be the best travel days within the state ahead of Christmas. Then, another push of moisture will move through around Christmas Day. We don't see nearly as much humidity with that next one though, so the chance for snow will be less than this first system, and again focusing on the central and northern mountains the most.
Being realistic we won't and can't say that Denver and the metro areas won't have snow falling on Christmas. It certainly remains a possibility. However, the chance for snow on the ground or actively falling isn't overly optimistic. The operational ECM which once showed several inches of snow Christmas night produced 0.00” QPF for DEN at 12z today, and its ensembles about an inch. The ECM has been underperforming the GFS this December anyway. The GFS has remained most consistent with this system producing little snow for the eastern half of the state.
The lack of snowfall for Christmas isn't much of a shock, as it fits with our history. Only 18 times since the late 1800s has snow fallen on Christmas Day in the city. Denver does not have snowfall on Christmas Day very often. Click here to read more about historical our chances.
Still some hope for snow this week, maybe?
Maybe. Again, a few locations may “get lucky” on Monday and see quick hitting dusting to a few inches, but most others will likely stay dry, or even see some rain.
The best chance for things to turn in the other direction may still be with the Thursday/Friday storm, but for now this doesn’t appear likely. While the trend has very clearly been for less snowfall with this system, there are still enough differences between the models keep some uncertainty going here. As it stands, the upper level support just doesn’t appear to be there with this system to produce any meaningful snowfall for the Front Range, even with the more bullish models. Still time of this to change, but it would require a little help from the storm out in front of it, and a good kick to the current trend, which is hard to do.
Enjoy your weekend, and get to the mountains if you can!
Thursday, December 18th 2014
A lot of folks jumping on the White Christmas bandwagon today, so I’ll begin this post with a word of caution before jumping into the details on what’s shaping up to be an active weather week across the country next week. Despite the excitement, there’s very little confidence in how much snow will fall along the Front Range and eastern Plains next week. It looks likely many across eastern Colorado will see at least two snow chances next week, but how much will fall remains very much in question.
That’s not to say we’re not pulling for a snow (yes, we’ve seen the EURO). In fact, nothing would validate what we’ve been saying for weeks better than the deterministic ECMWF: bitter cold and a good snow to end this otherwise quiet month.
There will be a series of disturbances affecting Colorado as we move into the weekend and next week. Timing and strength of each of these systems have been varying greatly run-to-run in large part due disagreements on what happens when they get east of Colorado. A system due to affect Colorado Sunday and Monday will eventually move into the Great Lakes and deepen. Where this system eventually closes off will greatly affect the eventual track of our end of the week Christmas storm. A lot to watch here.
Models have largely been dismissing our first system due in Monday -- but this one seems like it could sneak up on us. If you’re to believe the 18z GFS, it believes this could be the case too. The image below represents the jet stream location and speed on Monday evening.
As the strong jet stream energy moves over Colorado on Monday, the mountains will get some very heavy snow and wind. East of the mountains, the inevitable snow bands will set up in narrow, but very intense streaks. This far out, it is almost impossible to predict where these “streaks” are going to set up. However, those that do get in those heavier bands will see some good snow. While it’ll be a quick hitting storm, there’s quite a bit of energy with it. We’ll need to watch where models trend with the placement of the jet over the coming days, and also if we do get precipitation Monday, how much of that may at least begin as rain as per the GFS...
The next system will be moving in right on it’s heels Christmas Day. This is the system the EURO has latched onto for a good snow across eastern Colorado, though its ensembles continue to be far less gung-ho here as well. The 18z GFS, which really grabbed onto Monday’s system, is now tracking the surface low too far north of Colorado Christmas Day for much of any snow in Denver, a similar issue we’ve seen with the Canadian. I’m curious to see if the EURO trends to the northern track or stays the course tonight.
There does seem to be enough model consensus at this time to at least introduce a chance for snow Thursday and Friday next week, even with differences in tracks. The EURO has been pretty consistent over the last few days, and it’s ensembles have been showing a pretty good trough digging into the west from the 25-29 for sometime now. Not all models are showing snow on Christmas, however, so a good amount of uncertainty exists.
Where there’s greater confidence is in a good mountain snowfall event over the next week. As we head later into the weekend the flow aloft becomes very favorable for snowfall in the north central mountains. Totals from 1 - 2 feet will certainly be possible through Sunday through Monday, with more snow likely as we head into the middle of next week.
Here’s the current 5-day snowfall forecast from FreshyMap:
Cold, cold, cold?
Next week is forecast to get progressively colder as we go, and all indications are the cold sticks with us into the New Year. Here’s today’s 12z GEM 850 hpa mean temperature ensemble control run for 12z Dec 29, and it’s mean ensemble run below.