Updated by Meteorologist Andrew Freiden (4:13am, 2/11/2016)
Updated by Meteorologist Andrew Freiden (4:13am, 2/11/2016)
Posted on 02/10/2016 at 09:45 PM | Permalink
Written by Meteorologist Ros Runner (6:00 PM, 2/9/2016)
It's been an interesting day of weather in many parts of Central Virginia with clouds, sun, rain, sleet, snow, thunder, and even a not often seen form of precipitation called "Graupel". So what exactly is GRAUPEL? Here is one of many great photos I received on my Facebook page today. This is from Amber Hallman Ryan in the Short Pump area:
Many people described what they saw as "Dippin Dots falling from the sky". Graupel is often called "soft hail" or "snow pellets" and is a winter form of precipitation that usually develops when the atmosphere is unstable. It starts as snowflakes that fall from the base of the cloud. The snowflakes encounter supercooled water droplets along their path to the ground and these droplets collect and freeze around the snowflake giving it a rounded appearance. Sleet is a clear looking pellet of ice while graupel is white in color and softer to the touch. While we don't see it all that often, it usually happens at least once or twice during the winter season.
Thanks to all of you who shared pictures with us via email, Facebook, and Twitter!
Posted on 02/09/2016 at 06:20 PM | Permalink
Written by Meteorologist Ros Runner (10:00 PM, 2/7/2016)
Although we had plenty of clouds around during the day Sunday, we stayed dry even with a powerful low pressure system spinning off the southeast coast of the U.S. That storm stayed far enough offshore that only southeastern Virginia has seen any rain along with a little sleet and some wet snow. That storm will move away tonight into the day tomorrow and our attention will turn to a more important system approaching from the west late Monday into Tuesday.
While this will not be a well organized storm system, there will be lots of energy in the upper levels in the atmosphere (coupled with some very cold air aloft) that should initially help to produce some rain showers by Monday evening. As the atmosphere cools later Monday night into Tuesday, we'll see the potential for some snow showers over the region. I think any significant accumulations of snow will be hard to come by since surface air temperatures are likely to be above freezing and ground temperatures will be rather warm. It's possible that in some heavier snow showers, minor accumulations could occur on grassy areas, cars, bushes etc. but at this point in time, we don't anticipate any significant travel impacts.
From Wednesday into next weekend, we will be seeing a very sharp dip in the jet stream (huge upper level trough) in place over the Eastern U.S. This will bring us temperatures that will be running 10°-20° below normal for several days. In fact, a reinforcing shot of cold, arctic air arriving on Saturday should send temperatures tumbling into the mid teens (if not lower) by Saturday night into Sunday morning. We may be hard pressed to even make it above the 32° mark by Sunday.
By President's day (February 15th), there are some signs that warmer air may begin to push back into the region. In advance of the warm-up may be a developing storm system approaching from the south or southwest. Depending on temperatures when the moisture arrives, this may be our next decent opportunity for a winter storm. Still too early to tell, but it's something we'll be watching in the week ahead.
In the meantime, be prepared for a week of cold and have your gloves, scarfs, and heavy coats ready to go!
Posted on 02/07/2016 at 10:57 PM | Permalink
Written by: Meteorologist Ros Runner (7:00 PM, 2/1/2016)
We have started the month of February on a VERY WARM note with highs in many areas today topping the 70° mark. We officially reached 72° at the Richmond International Airport. While we have another very warm day likely by Wednesday, temperatures will be dropping again later this week and it will be feeling more seasonable by the upcoming weekend.
Next week is looking very interesting as we see the longer range computer guidance showing a HUGE dip in the jet stream developing over the Eastern U.S. by the 9th and 10th of February. This would bring a bitter cold blast of air into our region and that cold air would actually make it all the way south to the Gulf coastal region.
There also continues to be the threat of a storm system that *COULD* develop somewhere near the East Coast around February 10th. The latest run of the European model is showing the storm developing but staying fairly far off the coast. Perhaps close enough to bring us a brush with some light snow. Even without the storm, there may be enough energy in the upper levels of the atmosphere to help produce some snow showers in central Virginia by the middle of next week.
This is a good reminder that winter is far from over. While we are enjoying an opportunity to thaw out from the recent big winter storm, we still have a ways to go until Spring arrives. If you're wondering, Spring begins on March 20th at 12:30 AM. Something to look forward to if you are not a fan of winter!
Posted on 02/01/2016 at 07:16 PM | Permalink
There are some hints in the model guidance that Feb. 9-12 could turn "interesting". Won't keep you in suspense with that vague clue, but could be another winter storm long-about that time-frame, which is long-about still a ways off, so way to early to wring hands and grind teeth. That's not good for you anyway. -Jim
Posted on 01/29/2016 at 05:59 PM | Permalink
Written by Meteorologist Ros Runner (6:00 PM, 1/26/2016)
After a very cold and stormy period in the last week to 10 days, Mother Nature is going to be giving us the opportunity for a late January thaw. While temperatures will cool slightly over the next 2-3 days as a cold front moves through the area Tuesday morning, we are in store for a HUGE warm-up by this upcoming weekend that should last into at least Tuesday of next week.
You'll notice in the image below, the forecast Jetstream position this upcoming Sunday shows a sharp dip in the jet stream over the western United States. This is where the cold, stormy weather will be occurring. We'll see the opposite pattern in the eastern United States with a ridge of high pressure in the upper levels of the atmosphere. At the surface, winds will be steadily blowing from the south and southwest helping to boost our temperatures into the 60s for at least 3 days.
Beyond Tuesday, it appears the cold weather will return during the first week of February. As the colder pattern takes hold again, we'll be closely monitoring the potential for more winter storms. No imminent signs of this just yet....enjoy the warmer weather that lies ahead!
Posted on 01/26/2016 at 06:24 PM | Permalink
Written by Meteorologist Ros Runner (7:00 PM, 1/25/2016)
Our most recent winter storm is going to be one that we all remember for a very long time to come. It was our biggest storm since the snowy winter of 2009-2010. In terms of total snowfall in one storm, we have to go back to January of 2000 to find a storm of comparable size and magnitude. Below is a regional map showing snowfall totals across the Mid-Atlantic region: (Courtesy of the National Weather Service Office in Wakefield, VA)
Take note of the large area of 24"-30" totals in northern Virginia with some areas west of Washington D.C. receiving more than 30" of snowfall. Just amazing!
In central Virginia, this storm had two distinct phases with phase one bringing with it heavy snow, sleet, and some freezing rain. Phase two turned out to be the worst for many of us dumping more snow than we received in the first phase. This was thanks to a persistent, slow moving snow band that developed on the western side of the slow moving storm. You can see that orange shaded area near the I-95 corridor including all of the Richmond metro area. Many areas in here saw anywhere between 12" and 18" of snow with some reports as high as 20" around Glen Allen.
Here is a closer view of those totals around metro Richmond. You can clearly see the effect of Saturday's slow moving heavy snow band around Richmond. (Courtesy of the National Weather Service in Wakefield, VA)
The Richmond International Airport officially received 11.4" of snow out of this storm. This will rank as the 11th highest storm total on record since the records began in the 1897-1898 winter season. It also surpasses our seasonal snowfall average of 10.3".
Posted on 01/25/2016 at 07:27 PM | Permalink
Posted By Andrew Freiden 8:03am 1/24/2016
From around noon through 6pm it was snowing furiously across Metro Richmond. Check the radar loop:
Snow was coming down at 1-2" per hour in the heavier bands.
So: Was it a blizzard? Not quite. Here's why: The yellow text is National Weather Service "Blizzard" Criteria, the Pink is what happened in Richmond.
Other than winds being 10mph too light, it was REALLY close. We've been calling it a mini-blizzard. Thank goodness there wasn't much snow or ice stuck on Trees from Friday's storm. We seem to have avoided any major power outages.
Posted on 01/24/2016 at 08:44 AM | Permalink
The computer models are battling it out for how much snow could tally up from the Friday-Saturday winter storm. The European model has been showing a very cold solution, with much more snow for central Virginia, although the GFS model is no slouch, also predicting significant snowfall. The big difference is track and strength, which ultimately leads to differences in upper-level warming that will likely induce some changeover from snow to sleet and freezing rain for the Richmond area. The Euro shows less of this than the GFS, which is a tad warmer overall. Regardless, the reality will probably end up falling somewhere in between, but this "battle-royale" will be interesting to trend-track over the next couple of days!
The GFS model, while trending a bit colder, is the warmer of the two models. Heaviest snow would accumulate west and northwest of RVA, though our fair share would also be likely in the metro area. Ice on top of snow could pose additional issues.
The Euro model shows those areas in bright purple hitting the jackpot for heaviest snow totals. We'll see.
Remember, these are just the model outputs as of today (Tuesday) and will most likely change quite a bit over the next day or two. Stay tuned to NBC12 on TV and online for the latest updates. -Jim
Posted on 01/19/2016 at 08:33 PM | Permalink
Written by Meteorologist Ros Runner (12:45 PM, 1/19/2016)
There is no doubt that a major winter storm is going to be targeting Virginia later this week. Precipitation probabilities are at 100% for Friday and remaining very high into the day Saturday. Unlike other systems that we have seen so far this season, this one will be a slower mover. It is going to bring with it huge amounts of precipitation, and there will be plenty of cold air available.
As is typical in many winter storms here in Virginia, the I-95 corridor is where uncertainty is often the greatest....and this storm will be no exception. The powerful storm will be tracking into our area from the south and hugging pretty close to the coast. This isn't usually an ideal track for a huge, all snow type of storm for Richmond. When the storm tracks closer to the coast, it does bring in some milder air in off the Atlantic at the surface and aloft. Ground zero for that "battle ground" between the snow/mix/rain line is usually near the I-95 corridor and the City of Richmond.
In recent days, the European (ECMWF) forecast model has been very consistent in showing some big totals of snow over a good chunk of Virginia. Here is a look at last nights run of the European indicating 1-2 foot plus snow totals over much of the Virginia Piedmont, Shenandoah Valley, and northern Virginia into the Washington D.C. area. It also indicates some heavy totals around the Richmond metro, although the totals may be a bit inflated when you consider there should be some mixed precipitation involved closer to Richmond. Much lesser totals the farther east you go away from I-95 due to warmer temperatures.
The GFS (American) model has been a much warmer solution in recent days suggesting much more liquid versus frozen precipitation for metro Richmond. On the flip side, the GFS has said all along that this storm was going to be a big snow producer for the western and northern parts of the state. As of 12z this morning, the GFS has shown a SIGNIFICANT SHIFT toward the colder European model idea. It still indicates a high likelihood of mixed precipitation during the event here in metro Richmond with mostly snow not all that far to the north and west of the city. Here is the latest snowfall potential graphic from the GFS...keep in mind that while these totals do look much more robust for Richmond, there will be some mixed precipitation involved which could compact snowfall totals in the long run.
The Bottom Line: We are going to have a major winter storm on our hands with snow arriving before sunrise on Friday. We could see periods of heavy snow through a good bit of the day on Friday with metro Richmond eventually mixing with or changing over to sleet and perhaps even some rain. This would be particularly true to the south and east of the city. There will likely be a tight gradient of snow/sleet totals from the west end of the Richmond to the east end of the city.
We will continue to monitor model trends and will be issuing our first "SNOW FORECAST MAP" later today starting on NBC 12 at 5pm. Be prepared for a storm that will likely cause significant (if not impossible) travel beginning on Friday, through the day on Saturday and lingering into Sunday morning.
-Meteorologist Ros Runner
Posted on 01/19/2016 at 01:05 PM | Permalink