Wintry mix moving in (10 pm update)
UPDATE 10 PM: Precipitation is moving in faster than projected, already along Interstate 81 in Bristol and Abingdon. A mix of rain, freezing rain, sleet and snow will likely develop along the I-77 corridor within the next 1-2 hours and spread into the New River Valley by midnight and the Roanoke Valley shortly after midnight. Click on Radar/Future Cast at right for the latest on its progress. END UPDATE
Winter weather advisory expanded to include all of the region along/east of the I-77 corridor, including the New River and Roanoke valleys, Southside, and north into Alleghany Highlands and southern Shenandoah Valley. Ice accumulations of up to 2/10 inch and sleet/snow accumulations of up to 1 inch expected.
For the second time this week, a low tracking well to our northwest will spread moisture over cold air at the surface. But there is something different this time than Tuesday morning. High pressure, centered over southeast Canada but also bulging southward east of the Appalachians (shown as an “H” on the mid-morning map of the North American Model at left), is better positioned to push in cold, dry air at the surface, even as milder, moist air moves over the top. This is a big part of why the winter weather advisory covers a much wider area than Tuesday morning, with somewhat larger amounts of ice expected, possibly a tenth or two of an inch, and maybe some snow and sleet of less than an inch before it begins. As the moisture moves in after midnight, significant evaporational cooling is expected to bring temperatures rather quickly down to near the freezing mark. Early precipitation may be a mix of rain, freezing rain, sleet and snow, with more sleet and freezing rain as milder air aloft and colder air at the surface becomes established, and later on Friday morning more freezing rain and rain depending on local, subtle differences between locations that wander up to 33-35 degrees and others that hang at or just below the freezing mark. Just because you see no ice on the road, sidewalk or trees at your house doesn’t mean you won’t see some as you drive to somewhere else.
With sunshine and temperatures having reached the upper 40s and low 50s in much of the area, road surfaces will hold in some heat, so won’t most freeze over immediately. As is typical, higher elevations, protected valleys, and shaded spots on roads will develop ice first. If there is substantial sleet or snow on the outset, slushy conditions may develop, even on warmer road 
surfaces in lower elevations. A general rule of thumb for the early morning hours of Friday would be to expect widespread light icing on roadways- above 2,500 feet in elevation, patchy ice between 1,200 and 2,500 feet, and spotty icing below 1,200 feet, with more road problems if sleet/snow becomes heavy enough to slush up roads. Exposed objects such as trees and power lines will develop icing quickly just about anywhere the air temperature drops to 32, but at this time, amounts are not expected to be significant enough for large-scale power outages or tree damage. High elevations along the Blue Ridge – Floyd County/Bent Mountain come to mind – may have the greatest risk at some 0.25 or greater ice accumulations, generally considered the bottom line for significant tree or power line issues with icing. Roanoke city often floats down to about 33 or 34 degrees and escapes major ice problems in similar previous storms, but there may be just enough cold air wedging and evaporational cooling this time to even put some ice on the trees in lower elevations of the valley. (At left, inset map shows 50+ percent chances of .01 inch of ice in shades of blue, as determined by the Hydromteorological Prediction Center.)
The persistent wedge will only allow temperatures to struggle upward on Friday – not like Tuesday’s vault into the 40s and 50s with only a weak, easily scoured-out wedge of residual cold air in place. It may only crawl into the mid 30s in the Roanoke and New River valleys on Friday, and some particulary iced-up areas may actually not get above freezing. Another round of rain will mostly go southeast of our region late Friday night and early Saturday, but enough will move into Southwest Virginia to pose new ice accumulation potential to any locations that don’t get above freezing or only slightly do, then drift back downward. Locations north and west of Roanoke have the greatest chance of additional ice Friday night and early Saturday, though it appears amounts will again be light.
It looks like there will be two storm systems next week – one about Monday night/Tuesday, the other about Thursday or so – that will again ride the line between rain, ice and snow in our region.
February 21, 2013 - 5:04 PM
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Hope it’s rainfalln that takes us out of this winter along with seasonal temps.
I could definitely use a break from these twice-a-week borderline muck storm systems.
We are 37 here at supper time with calm winds! More clouds have come in and the sky looks like it could snow. Hoping for no ice!
Kevin, I think that sentiment could go for everyone in the area.
Hey Kevin in an unusual Storm system like this who stands the best chance for snow the lower elevations or the higher elevations ?
seems like every thursday friday timeframe we get this muck and it’s messing with my travel schedule!
I honestly don’t understand the call for significant icing. Yes there will be some but almost all models show the air aloft will be cool enough to support snow. At least north of Blacksburg.
Higher elevations will still have the better chance of accumulating snow, though it may also come down more to north-south location (favoring north) rather than purely elevation. The warm air aloft appears to be too great, though, to allow for a long period of snow (you can remind me of that when someone has 3-5 inches at mid-morning).
Lower elevations, however, do sometimes have a better shot at getting sleet instead of freezing rain, because moisture has that much further to fall in sub-freezing air and freeze into pellets. There was a small event in January 2006 I think in which Bent Mountain had freezing rain and was totally iced up while Roanoke got about 1/2 inch of sleet and not much freezing rain.
Ice storm lover: Most of the soundings on the models show the warm nose coming in ABOVE the 850mb level, so the 850mb 0C line isn’t necessarily a good marker for snow. But could lend itself to more sleet than freezing rain early on. The NAM and GFS do retreat even the 850mb freezing line northward by mid-late morning, while leaving the surface freezing line farther south.
Indeed chances of some accumulating snow will be better the farther north one goes.
Thanks Kevin I wish it would be snow but i know i am not alone
What are the evening models saying about tomorrow Kevin?
To illustrate my point in comment 9, here’s the 7 a.m. sounding over Roanoke on the 12Z GFS.
http://blogs.roanoke.com/weatherjournal/2013/02/advisory-expanded-for-fri-am-ice-threat/skewtroanoke0222/
If you follow the diagonal line upward from 0, that’s marking the freezing mark (32F, 0C). The line stays on the left side of it past 5,000 feet, marking below-freezing temps. But where I have circled, there is a little “nose” between 5,000 feet and 10,000 feet that on the right side of the diagonal 0C line, which marks temps above freezing. That is the “warm nose” that is expected to make sure we see more sleet and freezing rain rather than snow … if it’s right. We’ll see.
Evening models don’t run til later (9 pm NAM, 11 pm GFS).
Kevin, is there a rule of thumb about how much precipitation is needed for a given amount of ice?
Ice accretion is very complicated. More freezes quickly the farther temperatures are below freezing. Light to moderate rain leads to less running off before freezing than heavy rain, but heavy rain provides more moisture that can freeze. And then there are variations in temperature of exposed objects. There are some models that attempt to simulate this but are not widely available.
Ice accretion won’t exceed total rainfall, and will usually be something less than total rainfall, allowing for runoff — which will be more if rain is heavy and/or temperatures are nearer the freezing mark.
With rain nearing Knoxville on radar, wondering if we get off to a bit earlier start than expected overnight.
Kevin,
We have a 7 AM flight out of ROA tomorrow and will be driving in from Pulaski Co. What are the chances we’ll make the flight and that the flight leaves on time???
Best guess??
I posted some forecasts from Channels 7 and 13 at the end of the previous thread, FYI. Then I watched Channel 10 at 6:15, and Jeff Haniewicz is also forecasting some sleet or freezing rain in the pre-dawn and early morning hours. but I am pretty sure that he also forecasted a Roanoke high of 38!! Go Jeff H!!
wd, you should still be awake. Your mission, should you choose to accept it, is to look at those forecasts and what others have opined here, and then say it. You know …… “NKWIGTH” …. or “TDKWIGTH.”
One very interesting note from the Channel 10 forecast model. What I thought Channel 7 was saying and what WSLS’ (Channel 10′s) forecast had were just the opposite of each other for ice accretion. WSLS showed tiny ice amounts like 0.03 and 0.02 for Roanoke and Blacksburg, and similar itsy amounts for even Wytheville and Lexington. Jeff H did mention that high spots along the Blue Ridge Parkway (most likely from the Bent Mountain area and extending SW) might get up to 0.2 inches. But the king of the cities on his map was Martinsville!! 0.13 inches. Danville: 0.10 inches. Lynchburg: 0.07 (a little James Bond Theme music, please ….).
joe and Quags!! You are being paged. By lakeman, comment 17.
Do you think there will be enough icing for school closures?
Won’t make any guesses on when flights leave or whether schools open or close. Much more qualified people than me should make those calls.
If you travel to Roanoke for 7 a.m. flight from Pulaski, worst section of highway is often the Christiansburg to Ironto stretch on I-81. Beware of all overpasses even if highway seems fine.
Regardless of what type of precip falls where and when, the forecast models of all 3 TV channels showed large amounts of time (especially midday tomorrow) when there would be no precip at all, especially in Roanoke city and the R. Valley. That would be nice for us letter carriers, especially the guys and gals who walk. A couple of bloggers mentioned that they are not expecting the vast majority of roads to be a problem at all. I agree. Temps warmed to the low 50s in the Garst Mill Park area at 4:40 PM today, and that along with brining by VDOT will both help a lot.
And I also agree with Kevin. If temps were to drop to 28 or 29 (or heaven forbid even lower!!) with freezing rain (I have witnessed that decades ago, and hope I never do again), then the roads would become skating and skidding rinks.
I think the worst of it may be over by mid-morning.
My temperature is 41º and dew point is 10º. Its very quite and still outside.
***** Following is detailed stuff about I-81. Please skip it if not interested. Lakeman, KM brought up a terrific point, about the overpasses. They are much more likely to ice up than any other stretch of road, IMHO. During the warm weather months I go up and down I-81 a lot to your county, and that big stretch (starting from Exit 118, Route 11/460 Christiansburg exit) down-and-up-and-down-and-up-and-down-and-up-and -then the loooong 3-mile all downhill from Milepost 125 to the Ironto exit is a very tricky section. EVEN IN GOOD WEATHER! One overpass is near Milepost 121, where I-81 goes over Den Hill Road. Might be another one near Milepost 124 or so, where I-81 goes over (or is it under?) Seneca Hollow Road. Actually there are more overpasses between the Ironto exit (Exit 128) and Exit 143, Route I-581 exit. There is a big overpass (really a bridge) on I-81 between Exit 140 (Route 311 exit) and Exit 141 (Route 419 exit), over a sort of gorge. That might be the most treacherous section of all in the predawn hours.
Lakeman,,,
Leaving,,,and leaving ontime would be the operative
phrases to consider..
If the NWS service fcst is close as to the start time
of the freezing rain and ice pellets it could be problematic.
What you want to do is check with the carrier tonight and see
if all flights made it in this evening (overnighters )which im certain your flight is and which weatherwise looks solid)
However , if the carrier for whatever reason thinks the airport
will be a skating rink for much of the day all bets are off.
Call the carrier this evening (or you can tell me what flight it is..
I can tell you if its cancelled early.) Tomorrow being Friday and a normally
heavy travel day I cant imagine it would cancel…however you might be ready
for possible long delays. Freezing rain with added in pellets is the worst kind of icing on the ground from an operational standpoint…there are some of those scenarios its simply a no go. Hope for above freezing conditions quickly..Or a quick de-ice spray and hit a gap in the precip.
Here’s the link to Roanoke Regional Airport. Looks like a few flights have cancelled on Friday, but nothing at 7 a.m., so far.
http://www.roanokeairport.com/
Delta has cancelled early flight,,,
but my guess is that that was an operational
decision based on empty seats on the 11am..(11:07)
They cancelled the 9:55 pm flight inbound tonight…leaving no airplane
for tomorrows outbound.
They have 2 originating flights…one to LGA the other to Atlanta..
Looks like they are gonna cut their losses.
Kudos to ROA…very well maintained site.
Kevin, the HPC map you shared showed a strong probability of icing in far SWVA and even East TN. This is contrary to what the forecasts are saying. We have been hearing an all rain event for us but there was a mention of possible freezing rain in the afternoon update. Does it appear icing may be further west into our region or is this HPC map overplaying the chances? WE are at 36 currently with a projected low of 33.
VT spread the roads on campus with ice preventive around Miller Time this afternoon. So far only a half dozen school delays according to WDBJ, but I bet that will rise.
Have a flight out of Charlotte tomorrow at 4pm, plan on leaving 10 or 11 or could go down tonight and get a hotel.
Any thoughts on travel conditions tomorrow?
Thanks
i am only a 7th grader who wants schoool to be out tomorrow. plz snow and ice. it is only 35with a humdity of 60% in buchanan
Dirckcox: Beware Fancy Gap on I-77 if you take that route. Conditions should improve through the day, so the later the better, but there may be pockets that hang on longer.
Michael Hoback: HPC map often seems to miss a little on precise topographic features in the area. But it’s hard for me to imagine your location would be at zero percent for even .01 inch of ice.
Very large ring around the moon tonight and a beautiful, sunny day today both signal lots of moisture tomorrow.
Just in case anyone’s interested pavement surface temps are running above air temp currently. 2 examples, I-581 NBL MP 5.5 air temp is 42.4º and surface temp is 44.2º. On I-77 near me at MP 16.9 SBL air temp is 40.4 and surface is 44.2.
Radar shows precip (mostly rain) about to reach Bristol. May be on you before very long, Michael Hoback. Dry air will eat it some headed northeast, but still may be on track for midnight or even earlier arrival Roanoke/NRV.
Dirck…agree with Kevin..
Probably above freezing for most of the
area by 9 or 10..
and of course Fancy Gap is “right foot
poised for tapping “territory…
I have a few reservations about the temps…
south- southeast winds at 5000 feet..
even at 10000ft temp is 32F with winds more westerly 45kts.
I think its a possibility itll change over fairly qkly to
all liquid in the am…just a hunch.
‘Nother nor’easter heading into the forecast area this weekend with
a decent stripe of frozen precipitation progged along in the NW edge
of the precipitation shield.
Forecast element: storm-total snowfall
Deadline for entries: 7 PM EST SAT…23-FEB-13
Verification period begins: 12:01 AM SUN…24-FEB-13
Verification period ends: when the snow stops.
Details at…
http://newxsfc.blogspot.com/2013/02/winter-12-13-storm-5-call-for-forecasts.html
—
** Early announcement b/c of other commitments tomorrow evening and
an earlier than usual deadline for entries. **
According to NWS the air temp at Abingdon is 47 and dewpoint is at 20. Temp here at the Chapel is 36 but I do not know the dewpoint. Moisture is moving fast this way.
If I were making a more precise guess, I would say Roanoke city (ROA) goes from sleet to rain and bottoms out at 33 or 34, with light icing in surrounding higher elevations 1200 feet+ (my trees).
Floyd County/Bent Mountain always seem to maximize these icing situations, with some southeasterly upslope contributing. And I’m pretty sure Blacksburg bottoms out at 30-31 or so.
But the margin for error is, quite literally, thin ice.
Well I’m not going the conservative route. I fully expect Ice Storm warnings to be up South of Roanoke by midnight. Check out my facebook page – Blue Ridge Weather for full thoughts.
Meghan…keep an eye on it..
I just looked at stations West and Northeast
of Roanoke for tomorrow…
It looks like the ice may change over to
rain briefly midday from Charlottesville to
Dulles Airport (more pertinent to Roanoke and Valley systems)
Looks like some forecasts expect it to change back over to
ice again around noon…you can only hope..(But remember July is a bad
time to be in make-up classes!!)
Keep your ears to the radio…when I was in the 7th grade I shared your snowy soul !!! Now do your homework..because if you dont you-ll be cursed!..
0z NAM Hi-Res still showing a period of some kinda frozen precipitation. (Black dot is Roanoke)
Valid 4am Friday morning:
http://i.imgur.com/a3v4k87.png
It is already down to 35-36 here, is that colder than expected already?
Bristol ..precip now hitting the surface.
4 to 5 hours earlier than NWS fcst..
Based on that..and its steady advance..
Id say ROA precip starts not long after midnight..
will have to watch where those temps snuggle up
to the rising dew points..
and how quickly the air gets saturated…
Hickory may be a good benchmark to watch as well..(HKY)
In other words Kevin (at 37) I agree..
Sorry , I missed that..
But at least its independant reasoning!!
WDBJ7 reporting 43 in roanoke right now (9:25). Is it really going to drop 11 degrees tonight?
Cole: I think it drops at least 8-10 degrees of that easily with the level of dry air aloft and precip falling through it.
Trevar: The difference in your temp at 1400 feet in Cave Spring and the Roanoke Regional Airport temp 300 feet lower is already a preview of how things could be very different over short elevation differences in the AM.
Joe – good comments for Meghan above. Being a former 7th grade teacher, I know what Meghan is going through. Besides doing your homework and keeping an ear to the radio, wear your jammies inside out and flush ice cubes down the toilet! Teachers like snow too! (not ice).
Just walked the dogs – Johnny – I agree – very quiet and still outside. My temps are at 33 with humidity now up to 44%. I couldn’t see the moon – covered by clouds.
It’s 42 at my location downtown. Dewpoint is 20. Plenty of room for cooling. But I do think Roanoke City proper will be mostly spared. We’ll see.
Cole …Im very doubtful…
at least in Roanoke proper…
Lots of evening energy can still get
trapped in there as thicker clouds
arrive early..
Freezing level over Bristol is about 10,500 feet
with interpolation.
Saw that VT had brined their roads on the drive home tonight but not the Town of Hokieburg streets. I brought work home in the event that the evil ‘i’ word happens.
Johnny near KHLX: Thanks very very much for those road surface temps!! Any chance that you could awaken about 5 AM tomorrow and do it again?? LOL
Seeing multiple reports of sleet in NC right now.
Road temps are something that should be
made available through the DOT…
Im a huge advocate…
It would be a tremendous help in moving traffic
and planning trips/routes.
Lets face it,,Where the rubber hits the road is
also where the ice hits that road.
I remember a similar storm setup in the 80′s. With that storm there was more moisture and a deeper level of cold air. I worked in Marion and lived in Emory so it was 86 or 87. Wytheville had 16′ of snow, Marion had 4′ of sleet and Abingdon had 1′ of ice with power outages. Do not think this one will pan out like that but this is a common pattern with cold air trapped to our east.
The winter weather advisory earlier said up to an inch of snow and sleet now it says up to 2 inches anything changed?
No ice
I’m with Zach on the Ice Storm Warning. Potential is there.
Lakeman…check with airline or ROA website for flight status. If it’s icy, the runway may be too slick for operations as ROA has fairly short runways and high approach minimums. Also, in some instances, the airlines will rebook your flight at not additional cost due to inclement weather.
I just updated the QWC website with my thoughts and Zach’s ice map. I have a hunch that we could see a serious winter weather event around March 2-4 as many others have been saying.
One more day on the mountain and then home.
Temp is 27 and its still clear outside.Gonna crash for the night.Guess it will be doing something when i get up in the morning.Just calling for a light mix up this way.
temp = 39.2
dewpoint = 25.8
This one is gonna be close here in the city.
7 p.m. balloon sounding at Blacksburg showed -30C dew point less than a mile up. Lots of dry air up there for evaporational cooling to bring temps down upstairs.
Temps on my PWS have risen a degree or so in the last 15 minutes. Wind has also picked up out of the ENE.
Love the blog Kevin. I got into meteorology for the European models.
Here is the gist of the TWC hourly forecast for Roanoke city (“my” 24017 zip). Right off the bat it is suspicious because it has a 0% chance of precip through 3 AM, then only a 10% at 4AM with temp all the way down to 31. But then they jump on board. At 5AM it shows a 60% chance of “Wintry mix”. Temps steady at 31 right through the 9:00 hour. POPs go 90%, 100%, 90%, from 6 to 8 AM. Then back to 60% and 50% with temp at 32 at 10:00. Description at 9:00 changes to “Light wintry mix.” 11:00 is basically the same as 10:00 except the POP drops to 40%. At noon things finally show an improvement. 40% chance of “showers” with temp of 33. 35* and 40% at 1 PM and 38* (!!!) and 40% at 2 PM. From what I saw earlier this evening these POPs are way too high, but maybe they will be verified.
Lee: That’s like my wife’s joke that she can’t keep me from looking at models on the Internet at two times of the year — winter and storm chase.
I’m just not seeing this one here in Galax…still 39* and dew point of 13. Loooong way to go for us to get freezing precip of any type in here. We were 51* today so lots of warming took place. Time will tell…
Love it! Keep up the good work.
It can sleet with temperatures into the low 50s under the right circumstances. Wouldn’t be surprised at all if you started as sleet there in Galax. Lots of places in NC with similar temps have been.
TWC Hourly for Blacksburg. Again, a 0% chance of precip until 3AM. And this forecast was just updated at 10 PM, BTW. 40% chance of “Light wintry mix” at 3:00 with temp of 28*. If that somehow falls as rain instead of sleet, Hokieburg is in for a real mess!! Same POP and temp at 4 AM. Still a cold 28* at 5AM but POP skyrockets to 80% and description changes to “Wintry mix.”. 6:00, 29* and 90%. 7:00, 31* and 100%. 8:00, 31* and 90%. 9:00, 31* and 60% and description returns to “Light wintry mix.” 10:00, 32* and 50%. 11:00, 32* and 40%. At noon, things finally get warmer. 35*, 40% and “Showers.” 1PM 37* and 2 PM 38*, showers 40%.
KM, comment 67. At least she is not complaining that you are looking at “models” (in skimpy bathing suits!!) on the si.com website! :>)
Bobby asked if anything had changed with the forecasts tonight regarding snow accumulation. NWS has added a snow/sleet accumulation map that shows lots of 1-2 inch amounts around the region, especially north/east of Roanoke (though some in higher elevations just southwest too).
http://www.erh.noaa.gov/rnk/emer/emer.php
Our rain has started and now it has mixed with some sleet. NWS short term forecast has some sleet and f. rain mixing in but no accumulation of ice expected. Temp went up to 39 and now back to 36.
Sleetin
Ben G., My temps on the PWS also slightly creeping up….
Temp = 39.7
Dewpoint = 26.4
Brandon, comment 52. I sure do hope that you are correct!!
Thickening cloud cover is the prime reason you’re seeing the slight temperature rise. The atmosphere is throwing on a blanket, trapping some heat.
Sleet falling heavily now with some wet snow also. The deck is covered with ice pellets. Temp is down to 35 and NWS has now added freezing rain to our forecast. That is typical for Morristown NWS. Wait till is starts and then add it to the forecast. Sorry I am venting.
Do you think the early arrival of precip. and cloud cover will effect overall temps and p-type?
I am putting in my request for a day off tomorrow Kevin! Make that happen
. I would much rather have 1-2 inches of snow and sleet than any ice at all.
Not much, Todd. Same atmospheric factors at work. Air aloft just as cold and dry.
Crazy how it seems these little “get on ya nerves” systems we’ve got this year seem to come in earlier than models suggest. Might just be me. Seems like in years past they’ve been late. Probably just me.
Michael H, no apology necessary. If the NWS office in Morristown, TN has a history of doing that, then they deserve to be mocked. Usually in my experience, NWS offices bend over backwards to mention anything “possible.”
Radar loop definitely showing evidence of the leading edge of the precipitation eroding some as it hits the wall of much drier air aloft banked against the mountains, roughly along the I-77 corridor. May take a bit more time to moisten it up to the east. Seems likely sleet/snow is primary precipitation type early on in New River / Roanoke valleys — after perhaps a short period of rain in lower elevations — since it has become so in so many locations to the southwest with not as much cold, dry air aloft.
And,Kevin I bow down to you,as it is sleeting heavily here in Galax,temp is 39*…
Nobody bows to anybody in weather. The atmosphere humbles us all.
For a change, I am glad that the Fenway Park left field wall (the I-77 “wall”) is eating up the advancing precip. Remind me this spring and summer that I posted this now, because I will probably be commenting unfavorably about it then. Meanwhile, the temp here is a wonderful 39*.
It is eating it up — but the evaporation is also making the atmosphere aloft colder. More likely to be snow or sleet when it does advance and reach the surface.
This will be the last update from the Chapel tonight. Wintry Mix has turned back to primarily a cold rain. Temps around 34-35. The upper atmosphere warming is kicking in. I expect little or no ice by morning here. Those of you in ice, keep it slow and steady in the morning. We don’t want to lose any of you folks.
The Raleigh and Sterling radar sites are picking up light echoes over Roanoke/Lynchburg area now, with their higher tilt. So precipitation is beginning to fall overhead, but is evaporating before reaching the ground. May be a few hours before we see much at Roanoke’s elevation — earlier the higher up you are.
This drying … and the low over the Midwest weakening and pulling farther away … is why the forecast models have (mostly) been showing relatively light amounts of precipitation in our area despite this enormous slug that has been coming at us on radar.
Just my measured opinion…
but I dont think ice on paved surfaces
at ROA will be much if any issue..
a lot of residual ground heat especially under dark
paved surfaces.
IF there is any ice issue at the airport in the morn…
(some sources show it bottoming out around 34F)
It would be to raised surfaces…metal railings and
of course wing and airframes..
Bridges in cold valleys and higher elevations (getting to the airport)
would seem to me to be the biggest area of early concern.
Would generally agree, Joe. If there is a fair amount of sleet or snow, it could be slushy on valley streets.
Just stepped outside–dry.
Snowing here in C’burg
28º and foggy now @ 6:10. Started as sleet and must of snowed a little too. Nasty coating of ice on top. I don’t know if it rained a little and froze or if its just the fog freezing but its extremely slick. Accumulation around 0.75″.
Currently I-77 SBL MP 16.9 air temp 28.6º pavement surface temp 31.6.
I-581 NBL MP 5.5 air temp 30.9º pavement surface temp 34.9º.