Saturday, January 4, 2014

Very cold air on tap Monday- Tuesday

Friday was out cold day with high below freezing and lows in the lower teens this AM.

Moderation on tap today, maybe a little freezing rain in the AM tomorrow, showers then the NEXT cold air attack. We should make a run at 0, but may fall short. (3-5 degrees likely Tuesday AM)

Looking at my Winter outlook, not bad so far as we've not had ANY accumulation snow and the mean storm track has been to our west. We've had some sharp cold outbreaks, but the warmth has lasted long enough to keep things +3 or or so, with it being a much more active storm pattern going forward.

It seems like we will have break from any pending winter weather outbreaks for a while by weeks end and from there is where it gets dicey. Some think that we continue to have cold air JUST to our west, but timing will be continue to be off where it's cold and storms approach as the cold air is leaving. Usually, you will get burned on that type of pattern with eventually 1-2 major snow and ice events. Other thing the mean trough moves east (trough in weather = cold and storym) and we could get a nice 2-3 week run of cold and storms (and yes, snow)

If I had to chose, I'd lean to option one, repeating our pattern but 1-2 pretty big deal events for ice and snow events. I'd target Jan 20-Feb 10th as key times for winter type precipitation events.

If you have an outdoor thermometer-- let me know how low it gets at your house!

Sunday, December 29, 2013

Cold still coming-- Snow no chance.

Maybe some light snow, rain or flurries Tuesday AM, but no real shot of anything more.

Was totally wrong on the Thursday event-- won't do much of anything.

Cold air still incoming-- a few days 32 degree range.

Can't seem to break the cycle of Cold shot, cold air departs as storm approaches and then warm up for storm, back to colder temps. Need some blocking in the northern Atlantic to lock our cold air in.


Saturday, December 28, 2013

Cold is coming is a lock-- snow is POSSIBLE.

Merry Christmas and Happy New Year to all--

Dusting off the weather blog to do some updates.

December has been an active month with a few "winter type storms"..

Temps have been what I expected, slightly above normal. We are running a +3 on the month, but 2 days have bumped that up where the lows were in the MID 50's-60 ish rather than mid 30s or so. We'd be in my 1-2 range I thought if not. We should end up between 2-3+ for the month.

It has been much more stormy than I had anticipated. We should be 3-4 inches above normal precipitation wise by months end with the rain coming tomorrow.

More cold air is heading our way.

1. One model shows a round of snow Monday night into Tuesday AM-- this is ONLY the NAM and it usually stinks in this range. It be coating to a couple inches. There is some energy on the backside of a cold front that causes this. Not buying this-- but it's on the "watch" list.

2. Some VERY cold air comes in New Years Day-- highs in the 20's a couple days.

3. A stronger piece of energy comes in Jan 2-3. Models have been all over the place, but something called the ensembles have slowly agreed on a more southerly track that keeps the cold air in place (It's been an issue with no blocking to the north to hold our cold air in place.

The air is VERY cold and as modeled now, it's not a super wet storm with modeled precipitation being near .5 to .6 of an inch. However, with it being very cold aloft, snow rations could be more like 15-1 so .5 could be 7-8 inches.

Key issues will be how strong the upper air energy is and can we keep the cold air in place, but not TOO strong to suppress the storm to our south.


This is MUCH higher on my list than the Monday night event. :) Will update as needed...

Monday, December 9, 2013

Quick update: Ice wrap up, and maybe a little snow and sleet to end RAIN tomorrow.

We dodged  bullet-- had that morning sleet and ice been more intense, I think power outages would have been more common. Instead, things looked cool, pretty- whatever adjective you choose and life is pretty normal.

I'm sure most of you saw footage from the Eagles-Lions game. Pretty incredible that they were expecting up to an inch via forecast, and they got slaughtered with 8 inches in the 95 corridor from Wilminton, DE to the Linc on Broadstreet. This is still an inexact science and mistakes will be made.

Another wave passes through tomorrow. Should start as rain towards morning, could mix with a little sleet and end as a burst of snow. I think the snow idea is a bit far fetched, and you may see a few maps on FB bringing 1-2 or 2-4 inches down to our region. Overdone-- 64 north will be the region that gets the 2-4, maybe 3-6.  Will keep you posted, but our best case scenario is 1-2 hours of wet, big flakes falling that MAYBE coat the ground.

Saturday, December 7, 2013

Late evening Update-- Potential to get much more serious.

We had 2 options to prevent a big ice event. (Colder air was a lock)

1. Colder profile-- more sleet and snow.
2. Less stuff falling.

1. Profile has done a typical CAD where under 5k up has cooled a little and lasted longer while above will warm fast. At some point, the surface will be 29 or so and 5000k will be 50. WOW...

2. Models have trended wetter-- mostly. Minimum is .50 falling, max is up over an inch.


Most ominous is the RGEM-- Note this is in MM, and puts the 460 corridor in  25 mm, which is about an inch, give or take. Orange is right on top of 460.



Will update on FB on twitter from here. PM w any specific questions. 



Yo'-- Let's kick it. Ice Ice Baby


No big changes--

Snow and sleet develop north of 460 between 5 and 8 am tomorrow. 
Sleet, with maybe a few snow flakes, quickly changing to freezing rain develops southside Between 4am and 7AM.


460 north could see up to 2 inches of snow and sleet, mainly sleet. I suspect it's mostly freezing rain by mid afternoon, with a little sleet mixed in. For those wondering, sleet accumulates about a 3-1 ratio, so one inch of rain water  3 inches of sleet. I suspect that between .2 and .4 max falls as sleet. That's a half inch to about an inch and a quarter based on my best guess. 

Freezing Rain- southside will see a glaze to .25 at the most. 
460 corridor gets .15 to .40
Once you get NW Amherst County, Rockbridge, Fincastle north, .25 to maybe .60 could occur. The best moister wants to focus on that area JUST north of 460. Something to watch on radar tomorrow. 

Friday, December 6, 2013

Winter Storm Watches Hoisted-- Complicated forecast.

As is often the case, with our storm as some details clear up others become more murky.

It really seems like a mix of snow and sleet develops and begins a drift towards freezing rain, starting in areas to the SW and spreading north and northeast.

Drier air is a concern and where exactly the best lift sets up is a concern as well, because some areas that are expecting a decent snow and ice event COULD end up rather dry, with just freezing drizzle the bulk of the day. Anywhere from 460 south needs to be aware of this concern.

This will likely be a "winter storm warning" but will lack the total moisture to be a "big ticket event". The colder temps will make it a travel concern but major power outages, ect are not likely, especially from 460 south. North of there, snow and sleet should minimize ice build up.
Add caption
Yellow: Initial burst of sleet, maybe a little snow switching to Freezing Rain. up to a coating of sleet and snow, up to .15 ice build up.
Green:  Sleet and snow mix to start, Coating to 2 inches. Ice build up from .1 to .25 in hardest hit areas.
Pink;  Coating to 3 inches of snow/sleet. .15 to .40 ice build up. 

Yellow area includes: Martinsville, Danville and South Boston. 
Green area includes: Blacksburg, Lyncburg and Roanoke
Pink area includes: Northern Amherst, Northern Botetourt, Lexington, Staunton, Waynesboro.