Long Range Models Suggest Cold Wins Out For A While

New long range data has come into the weather center over the last week, and it looks like any warm-ups for the rest of March will be short-lived.

This morning’s GFS model is very similar to the last several runs before it, keeping colder than average temperatures around through the weekend, next week, and the week after next. While there will be some warmth into the start of this weekend, this morning’s GFS model has colder than average air (purple and blue colors) over much of the Midwest and Ohio Valley by next Tuesday:

mar13-gfstue

The GFS model also suggests that cold air sticks around into late March, including for Monday, March 25th:

mar13-gfsmon

Northwest flow and a persistent snowpack in southern Canada means reenforcing shots of cold air will keep coming for the second half of March.

A new ECMWF Weekly model run came in this afternoon. Like the GFS, it suggests below average temperatures will dominate for late March and early April. This afternoon’s ECMWF Weekly model says temperatures will be below average (blue colors) from this past Tuesday through next Monday:

mar14-ec1

The model also says temperatures will be below average in the Ohio Valley from next Monday through March 25th:

mar14-ec2

…and from March 26th from April 1st:

mar14-ec3

…and from April 2nd to April 8th (although not as cold as previous weeks):

mar14-ec4

The theme is clear: cold air will be a clear winner over warmth for the next few months. It is still too soon to make an outlook on the summer.

Thoughts On Snow Accumulation Tonight And Wednesday

We may be nearing mid-March, but we aren’t done with the threat of accumulating snow in the Tri-State. While the disturbance coming through late tonight and early tomorrow isn’t particularly strong, it will be strong enough to create snow showers and flurries around and after midnight.

Recent model runs have hinted at the possibility for localized bursts of snow for a few days now. Once of our in-house models, Microcast, has been very consistent with the timing and strength of this incoming disturbance. By midnight tonight, Microcast paints snow showers and flurries in and around the Tri-State (in blue):

mar12-12ammc

Microcast is also painting some shades of purple and pink, suggesting rain will mix with flurries. While this is possible, it is not likely given the forecast temperature profile of the atmosphere.

By 7am Wednesday morning, Microcast has several clusters of snow showers and flurries in the area:

mar12-7ammc

The ground and air near the ground will be cold enough to support a chance for accumulating snow at this time. With the morning commute in progress, slick or partially snow-covered roads, sidewalks, and driveways are a concern. Many will just see flurries and little to no accumulation while others that see snow showers may see 1/2″ to 1″ of snow by early Wednesday afternoon.

The risk for snow showers and flurries will drop dramatically by Wednesday afternoon. The latest run of Microcast has only widely scattered snow showers and flurries in our area by 5pm Wednesday:

mar12-5pmmc

This morning’s Microcast run gives nearly all of the Tri-State 1/10″ of snow accumulation or less through Wednesday afternoon:

mar12-adonis

While I agree with this model output overall, isolated 1/2″ to 1″ totals can’t be ruled out overnight and tomorrow morning in the heavier bursts of snow. The best chance for these isolated higher totals will be on elevated, grassy surfaces; accumulation on roads, however, is also possible in the next 24 hours.

Please use caution on area roads during Wednesday morning’s commute!

Update On Accumulating Snow Threat Tuesday Night And Early Wednesday

A Winter Storm WARNING has been posted for Fayette, Union, Franklin, Butler, Warren, and Clinton County from late Tuesday morning through 1pm Wednesday:

mar4-wsw

The rest of the Tri-State will be under a Winter Weather Advisory from 6pm Tuesday to 1pm Wednesday:

mar4-wwa

Light rain (especially after midnight) will mix with flurries tonight, and Tuesday’s forecast calls for mainly rain with some flurries in the morning. With ground temperatures at or above freezing tonight, accumulating snow is not a concern; accumulating snow, however, is likely late Tuesday night and early Wednesday.

For being this close to the Tuesday night/early Wednesday event, there is still great uncertainty about where the heaviest snow will fall in the Ohio Valley. The latest model data have trended farther south with the axis of heavier snow. Last night, it appeared the heaviest snow would be in northern Ohio and Indiana; that axis of heavier snow now looks to set up closer to I-70.

I will show you the latest model runs not to highlight specific amounts but instead to show you model uncertainties and where the heaviest snow – at least for now – will fall. Remember, this is NOT a forecast!

Our in-house model Precisioncast gives a wide range on totals from north to south; it suggests the southern-most communities in the Tri-State will see minor accumulations while many north of the Ohio River see at least a couple of inches of snow through Wednesday evening:

mar4-adonis

Another one of our in-house models, Microcast, gives most in the Tri-State about an inch of snow, but also blasts some Tri-State communities with snow:

mar4-mc

This morning’s ECMWF model – which has consistently been the most aggressive with snowfall amounts Tuesday night and early Wednesday – gives the Tri-State anywhere between a couple and a few inches of snow:

mar4-ecmwf

The latest outlook from NOAA’s Hydrometeorological Prediction Center gives the northernmost parts of the Tri-State a moderate risk of seeing 4″+ of snow through 7am Wednesday morning; according to this forecast, the rest of the Tri-State has a slight risk for seeing 4″+ of snow:

mar4-hpc

My Latest Forecast

For now, I’m thinking we’ll get a couple inches of snow Tuesday night and early Wednesday. The highest snowfall totals will likely be north and northeast of Cincinnati, and the lowest totals will be focused south and southwest of the Queen City. Visibilities will likely be reduced by snow falling early Wednesday. Snow will likely be wet and slushy instead of dry and powdery with this event.

This blog will be updated tomorrow…or as needed!

Thoughts On Accumulating Snow Potential Tuesday Night And Early Wednesday

Like I’ve done every snow event this season, I will hold judgement on specific amounts until we get much closer to the event. For this bout with wintry weather, we’ll get a rain/snow mix Monday night through Tuesday and snow Tuesday night and early Wednesday. No ice is forecast in our area with this mid-week system.

It is important to note that three different areas of low pressure will move through the eastern 2/3rd of the country between now and Thursday. Here is a plot showing the track of each low pressure system, as analyzed by NOAA’s Hydrometeorological Prediction Center:

mar3-lowtracks

The area of low pressure tracking out of southwest Canada will die before ever making it here. A different area of low pressure that develops over the Mid-South and Mississippi Valley will sweep through the Ohio Valley Monday, Tuesday, and early Wednesday. This area of low pressure will also die, and another area of low pressure will develop in the Carolinas Tuesday night and track just east of the Mid-Atlantic states Wednesday afternoon and Wednesday night. The low tracking through the Ohio Valley will be the driving force behind our threat for accumulating snow.

A rain/snow mix will develop in the Tri-State Monday evening  and continue through Tuesday. Very minor accumulations are possible early Tuesday, but rain will likely be the main precipitation type Tuesday afternoon with temperatures in the mid to upper 30s. Rain and snow Tuesday afternoon will transition to all snow Tuesday night. My forecast low for Wednesday morning in Cincinnati is 29°. Accumulating snow would be a much bigger threat if low temperatures were forecast to drop into the low to mid 20s. Nonetheless, our main window for accumulating snow will be late Tuesday night and early Wednesday.

I will share the latest model snowfall forecasts in this blog with you not in an effort to pinpoint specific amounts but instead to show uncertainty and where the focus for heavy snow will be.

Sunday morning’s NAM model keep the focus for heavy snow accumulations through Wednesday afternoon north of the Tri-State:

mar3-namsnow7pmwed

Notice the NAM’s forecast of 20″+ for the Washington D.C through 7pm Wednesday. This morning’s GFS model brings the threat for accumulating snow closer to Cincinnati but keeps heavy snow over northern Indiana and Ohio:

mar3-gfssnow7pmwed

Sunday’s morning’s ECMWF model is the most aggressive model with snow Tuesday night and early Wednesday:

mar3-ecsnow7pmwed

The ECMWF brings a swath of 5-10″ of snow up to the edge of the Tri-State. This model is an outlier, and – for now – I do not believe this is where the heaviest axis of snow will set up.

NOAA’s Hydrometeorological Prediction Center gives the Tri-State a 10% of seeing 4″+ of snow from 7pm Tuesday through 7am Wednesday, but chances for 4″+  of snowfall accumulation ramp up quickly northwest and east of Cincinnati:

mar3-hpc

For now, plan on accumulating snow Tuesday night and early Wednesday. The Tri-State is fair game for an inch or more of snow and potentially more if temperatures trend cooler than forecast early Wednesday morning.

I’ll update this forecast Monday afternoon!

Remembering The March 2, 2012 Tornado Outbreak

I remember the Blue Ash/Montgomery/Symmes Township tornado on April 9, 1999. I was in Blue Ash that night, and it was the loudest thunderstorm I had ever heard in my life. My home was not hit, but nearby friends’ homes were. In the days after that tornado, I helped clear debris, collect belongings, and provided a shoulder to cry on if needed. The damage was intense, but localized; you can still see evidence from the tornado if you look carefully at the trees across the street from Sycamore High School. That tornado is a big reason why I am a meteorologist today.

Before returning to Cincinnati, I tracked numerous severe thunderstorms and tornadoes in the Ohio Valley. I had been in numerous Storm Prediction Center “moderate” or “high” risks before. While last winter was abnormally warm, it wasn’t unusually stormy. Rain would come and go, and there was little to no snow. At the time, I remember meteorologists in this area joking about how boring the weather pattern was.

On the Monday before Friday, March 2nd, 2012, I was working the morning shift, and I noted the risk for strong and severe storms on Friday. Before March 2nd, there were other severe weather threats to our south and west. With a slight risk of severe weather (as forecast by the Storm Prediction Center) in place, an EF4 tornado hit Harrisburg, Illinois in the middle of the night on February 4th. News of this violent tornado in late February was – frankly – bit surprising given NWS and SPC forecasts; it also had me on edge regarding the forecast for March 2nd. Where forecast models handling everything correctly? As the week went on, the threat for severe weather on Friday increased in the Ohio Valley, but I remember forecast models keeping a focus for severe weather centered over southwestern Indiana, western Kentucky, and Illinois…in areas that had been hit hard by storms earlier in the week.

On the February 29th, 2012, the Storm Prediction Center had the entire Tri-State in a slight risk for severe storms and mentioning a threat for tornadoes:

day3

In the early morning hours of March 1, 2012, the Storm Prediction Center upgraded the Tri-State to a moderate risk and mentioned a threat for “long track” and “strong” tornadoes:

day2

The Ohio Valley remained under a moderate risk until 7:58am eastern time on March 2. At 7:59am, parts of the Ohio Valley were placed in a rare Storm Prediction Center high risk, but the Tri-State was not included yet:

day1-1

I remember setting my alarm for 7:45am on March 2nd just to see if the Storm Prediction Center would put us in a high risk. They didn’t at 7:59am, so I went back to bed for a couple of hours.

By 10:30am, I was back awake, and watched as the Storm Prediction Center put the Tri-State in a “high risk”, suggesting that long-track and potentially violent tornadoes were imminent:

day1-2

I was into work shortly thereafter. Until about 1:00pm in the afternoon, it was a “waiting game.” No supercells had popped up in our area, but we knew the powerkeg was about to blow. High-resolution models suggested rotating storms and supercells were going to explode in the afternoon, but they disagreed on exactly where. Between and 1 and 2pm, Tim Hedrick and I watched as three different supercells blew up in southwestern Indiana over the span of two counties in less than 15 minutes. When Tim says, “I’ve never seen supercells go up on radar that quick near here. Ever.” you believe him. In 20 minutes, Dubois and Perry County Indiana went from having just cumulus clouds to tornadoes.

A lot of the suspense about what was going to happen and where was resolved by 2:30pm in the afternoon; supercells in southern Indiana were producing damage, and there were numerous indications from spotters that the damage was extensive and the tornadoes were strong or violent. As a meteorologist, I knew there was a chance for this to happen, but until it had been confirmed, the magnitude of this event didn’t really hit me.

Between 2:30 and 3:30pm, we were just waiting for the worst. My tweets from to 2:30pm to 3:45pm became more and more urgent:

twitter3212

There were reports of tornadoes with the two supercells rolling up I-71, but the focus had to be turned to Ripley County suddenly as a supercell in Jennings County, Indiana pushed east. This cell would produce a EF-3 tornado and kill two in Holton:

TCVGholtonZandV2

Thankfully, the storm that produced a tornado in Ripley County would quickly die, but this event was just beginning for northern Kentucky and southwestern Ohio. While reports of tornadoes and funnel clouds came in from Carroll, Gallatin, and Owen County, the rotation in the northernmost supercell tightened quickly. The first, second, and only Tornado Emergencies ever issued by the National Weather Service in Wilmington were issued for this cell. Looking back at our severe weather coverage, I noticed my hand and the warning printout I was holding were shaking as I announced the first Tornado Emergency on the air. A family friend of mine several weeks later called me out on my hand shaking. She told me that was her first indication from me that this was going to be bad event.

By the time the storm was in southern Boone and Campbell County, damage was already being done; some of the debris from the violent EF-4 tornado in Piner/Crittenden could be seen on the FAA Doppler radar in southern Kenton County just before 4:30pm:

pinertdwrZandV-ZandVshaded

At first, the debris ball (shown at the end of the hook echo in the left side of the above image) wasn’t apparent. Data were only available from the FAA radar every 6 minutes on March 2, 2012, so word of the debris ball first came from the National Weather Service in Wilmington (who could see the radar data every minute). This debris ball on radar was the second sign to me (once storms were in the viewing area) that this would likely be a deadly and historic event. In the over 20 years I’ve lived in Cincinnati, I had never heard of or seen a debris ball on a local radar.

A second debris ball showed up on the FAA Doppler radar in southern Campbell County as the northernmost supercell hit Peach Grove, Kentucky:

peachgrovetcvgZandVwithmoscow

This storm went on to hit Moscow and Hamersville, Ohio, producing EF-3 damage and killing 3. Initially, this report of damage in Moscow was delayed; I remember it was at least 20 minutes between Moscow was hit and when we first heard about the damage.

After the tornado had caused damage in Moscow, fatigue began to become a factor. We had been on the air for more than two hours and reports of damage were coming in every couple of minutes. There was no time to be tired, though. 4 more tornadoes would occur after the damage in Moscow, including an EF-1 in Seaman, Ohio and two tornadoes near West Union. The rotation from each supercell in Adams County could easily be seen from NWS Wilmington’s radar just before 5:30pm:

mar1-seamanwestuniontor

By sunset, 9 tornadoes had raked across the Tri-State, and 3 of them were major tornadoes (given a EF-3 or greater rating):

mar1-tortracks

Originally, the Piner/Crittenden tornado was given an EF-3 rating; on the Friday after the outbreak, the National Weather Service upgraded the tornado to an EF-4. The Piner/Crittenden was only the 11th tornado in the Tri-State since 1950 to be classified as a violent tornado:

mar1-violenttors

16 Tornado Warnings and 5 Severe Thunderstorm Warnings were issued for the Tri-State on March 2nd, 2012. While this is a large number of warnings in our area on one day, it is a small fraction of the number of Tornado and Severe Thunderstorm Warnings issued in the entire country on March 1-2, 2012:

mar1-mar2warnings

After looking through the data, there are three things that stand out to me about the tornado outbreak of March 2, 2012. For the first time ever, the National Weather Service issued a Tornado Emergency for our area (not once, but twice). A Tornado Emergency is issued when a large, confirmed tornado threatens a highly populated area. Second, three major tornadoes were confirmed in the event. The last time 3 major tornadoes were confirmed in our area on the same day before March 2, 2012 was on April 3, 1974. Lastly, March 2, 2012 now stands as the deadliest severe weather day in the Tri-State since official NWS records began in 1950.

There is no doubt that this was the biggest event of my career so far and likely will be for the rest of my life. I still get emotional thinking about March 2, 2012. As a meteorologist, you do all you can do to get the word out about severe weather in the days and hours leading up to the event; when anyone dies on your watch, you take it personally and you wonder if you could have done more. I hope that something like what happened on March 2, 2012 in this area never happens again; unfortunately, events like these have happened and will happen again in time.

March Marks The Start Of The Tri-State’s Peak Severe Weather Season

Don’t let the snow, snow grains, thick clouds, and cold fool you; March is the start of our peak severe weather season in the Tri-State. In 2012, severe weather had a early, deadly start with a tornado outbreak on March 2nd. This event was unusually early in meteorological spring, but it is a reminder that severe weather can happen any time of the year and often happens outside of our main severe weather season.

Long-term trends suggests the potential for severe weather really ramps up in March, but most tornadoes and severe storms affect the Tri-State in the late spring and summer. Since 1950, the most active month for tornadoes in the Tri-State is April; it’s a close race for second place between May and June, and July is firmly in 4th place:

feb28-blog-torbymonth

23 tornadoes have been confirmed in the Tri-State during the month of March. 9 of these tornadoes occurred on March 2, 2012. If the March 2, 2012 tornado outbreak had never happened, March would have similar tornado count to August and November:

feb28-blog-torbymonthno322012

March is also not the most likely month to see Severe Thunderstorm Warnings issued, but the average number of Severe Thunderstorm Warnings issued in the Tri-State goes up each month from January through June:

feb28-blog-svrbymonth

On average, only two Flash Flood Warnings are issued in March in the Tri-State:

feb28-blog-ffwbymonth

May and June are the busiest months for flash flooding in the Tri-State, but flash flooding can still occur in the summer and early spring in long-duration heavy rain events or with slow-moving thunderstorms in the area.

While the week ahead looks rather cloudy and cold, our peak severe weather season is coming. These cloudy, cold days are the perfect time to prepare for severe storms. Make sure you have a severe weather safety kit with water, shoes, medicine, flashlights, and batteries.

Where The Upper-Level Low Goes Later This Week

There is no doubt that a cold front will sweep through the Tri-State late Monday night and early Tuesday. This front will bring rain, and it will – eventually – help to bring cold air from Canada into the Ohio Valley. In the wake of this cold front, an upper-level area of low pressure will get cut-off from the upper-level flow; in turn, this upper-level low will sit and spin over us until the jet stream can dislodge it to our northeast. While there is high confidence this upper-level low will stick around into the second half of the work week, there is great uncertainty about when it will leave.

Both this morning’s GFS and ECMWF agree on a subtle warm-up from Sunday into Monday. I’m forecasting a high temperature of 48° Monday afternoon and a low temperature of 36° Monday night. The latest model data suggests the temperature may rise late Monday night as low-level moisture gets pulled into the region on a strengthening east-southeasterly wind.

The GFS model has a surge in warmth midnight Tuesday in the Tri-State ahead of the cold front:

feb24-gfs12amtues

This morning’s ECMWF model is nearly identical to the ECMWF at midnight Tuesday; it has a surge in warmth ahead of the front and the upper-level low centered over the Mid-South:

feb24-ec12amtues

The forecast gets a bit messier nearing mid-week. This morning’s GFS model has the ill-defined upper-level low in the Ohio Valley by 8am Wednesday morning:

feb24-gfs8amwed

The latest ECMWF model run has the upper-level area of low pressure over Cleveland by 8am Wednesday…and brings slightly colder air to Cincinnati by then compared to the GFS model:

feb24-ec8amwed

The GFS and ECMWF aren’t really that different by mid-week, but the differences between the GFS and ECMWF become greater nearing next weekend. The GFS has the main upper-level low over New England and a secondary low trying to form over the interior Midwest:

feb24-gfs8pmthur

Also, notice the colder air (shades of blue) extending out of southern Canada. If you assume the GFS model verifies, this re-enforcing shot of cold air will mean clouds, flurries, and snow showers will stick around through next Saturday night and Sunday. This morning’s ECMWF model has a different solution; it says the main upper-level low is over Boston, has no secondary low forming west of the Great Lakes, and has no big surge of arctic cold air diving south out of Canada:

feb24-ec8pmthur

If you believe the ECMWF model, snow showers and flurries will stick around through Friday but will be gone by Saturday and Sunday.

Which model do I believe? I’m leaning towards the GFS for now, but I still give a nod to the ECMWF; I have flurries and snow showers in the Tri-State Thursday, Friday, and Saturday and only flurries early Sunday.

This forecast will likely need to be revised as next weekend nears. Regardless of which model you believe, winter is coming back later this week!

Winter Is Not Over: Long Range Forecast Looks Cold And Snowy

After a night and early morning with ice, low pressure is moving east, and high pressure is moving in from the west. This weekend will be reasonably warm and quiet, but cold air will pour in from Canada by the middle part of next week.

There are some differences among the newest model data on how cold we will get next week. This morning’s GFS model suggests temperatures will be 5-15° below average Wednesday afternoon (shades of blue and green):

feb22-gfs2manom18zwed

I agree with this model forecast. We’ll likely have high temperatures in the mid 30s Wednesday. When you look about 5,000 feet above the ground next Saturday morning, you’ll find temperatures well below average in the Ohio, Mississippi, and Tennessee Valley:

feb22-gfs850anom12zsat

If this model forecast verifies, temperatures may reach into the low to mid 30s in northern Florida early next weekend. This is a longer range forecast (with plenty of room for uncertainty), but it bears watching. Watch out, citrus crops!

This morning’s ECMWF model is also aggressive with a plunge of arctic air sweeping in behind Tuesday morning’s cold front. Notice the surge in warmth 5,000 above the ground Monday morning per the latest ECMWF model run (red and purple colors):

feb22-eculf8ammonday

I expect temperatures to reach to near 50° Monday afternoon before rain moves in from the west. We’ll drop into the 30s Tuesday morning and stay in the 30s Tuesday afternoon. The ECMWF model has plenty of cold air aloft at 8am Wednesday morning (yellow and green colors):

feb22-eculf8amwednes

We’ll be in the 30s all day Wednesday, and the 20s and 30s all day Thursday. Like the GFS, this morning’s ECMWF model suggests even colder air may drop into the Great Lakes and Ohio Valley by next Friday (green and aqua colors):

feb22-eculf8amfriday

If this model forecast verifies, we’ll start next Friday in the mid 20s and finish Friday near freezing.

Next week may be the start of a prolonged colder than average period. The latest ECMWF Weekly model released yesterday suggests the first full week of March will be colder than average in the Ohio Valley:

feb22-ecmwfweekly2

The ECMWF weekly also suggests that temperatures will be closer to average in the following week:

feb22-ecmwfweekly3

Of course, this is just one long range model and is not guaranteed to happen. While the latest ECMWF Weekly suggests much of March will be colder than average, I expect a wide range in high and low temperatures averaging out below average.

Enjoy a quiet, brighter weekend!

Everything You Need To Know About Tonight’s Ice Threat

Tonight is the night; love it or hate it, freezing rain is likely from mid-evening through early Friday morning. This has been a well-advertised event, but there are still some uncertainties regarding the amount of ice any given Tri-State community will get tonight and early Friday.

It is worth nothing that a lot of the ice that accumulates will melt as air and surface temperatures go above freezing tomorrow morning. Roads have been treated fairly well in and around Cincinnati; I am cautiously optimistic there will be few problems in the morning on roads. Sidewalks and cold, elevated surfaces will be favored to get ice accumulations over roads (especially the treated ones).

The National Weather Service in Wilmington has posted a Winter Weather Advisory for the entire Tri-State. It will go into effect at 8pm tonight for everyone and remain in effect for most in the Tri-State through 10am Friday; the advisory will remain in effect Fayette, Union, Franklin, Butler, Warren, and Clinton County through noon:

feb21-wwa

The main window for ice accumulation will be from 10pm tonight through 4am Friday morning, although freezing drizzle and very light freezing rain will be possible in the Tri-State as early as 7 or 8pm. Here’s my latest thinking on this event:

feb21-impacts

How much ice are we going to see? For the entire event, nearly all in southwestern Ohio, northern Kentucky, and southeastern Indiana will see between 1/10″ and 2/10″ of ice accumulation. This morning’s Microcast model run matches my thinking ice amounts:

feb21-iceaccum

There may be some isolated higher amounts in or just outside of the Tri-State, but this will be an exception more than a rule.

What will happen when less than 1/4″ of ice accumulates? You may see one or more of the following overnight and/or early tomorrow morning:

– Icy sidewalks
– Icy windshields
– Ice coated cold, elevated, outdoor surfaces
– Slick roads that are not treated

The following are unlikely this event:

– Power outages
– Widespread icy roads
– Widespread school delays

If you have an ice measurement, please report it! You can find me here:

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Update On Thursday Night Ice Threat

The threat for freezing rain, rain, snow, and freezing rain is still forecast Thursday night. Here in the Tri-State our main focus will be for freezing rain and rain. We don’t always see ice in the winter; this may be our best chance to see ice this season.

There is still uncertainty in the timing, positioning, and strength of this system. A 2° difference in temperature near or above the ground will make a big difference for what type of precipitation you’ll see and when.

For now, it appears our main threat for freezing rain will be between 10pm Thursday and 5am Friday morning. There will be a lot of lift in the atmosphere as this system pushes through the Ohio Valley; there may be some localized pockets of heavier freezing rain and rain Thursday night and early Friday.

Around 11pm tomorrow night, freezing rain will develop in and around the Tri-State, while rain will be favored to our south and snow and sleet will be favored to our northwest:

feb20-ice11pmthur

By 2am, the threat for freezing rain ramps up in and around Cincinnati:

feb20-ice2amfri

By 7am Friday, the odds of rain will be going up as the threat for freezing lifts into northern and central Ohio:

feb20-ice7amfri

While it may be precipitating heavy at times Thursday night and early Friday, air, pavement, and ground temperatures will be hovering around 32°. This limits the potential for ice accumulation tomorrow night some.

How much ice are we getting? It depends on where you live and which model you believe.

This morning’s NAM model keeps the best threat for ice accumulation northwest of Cincinnati and back into the Mississippi Valley:

feb20-namice

This morning’s GFS model is more aggressive with ice accumulation in our area, giving most at least a light glaze:

feb20-gfsice

This morning’s Microcast run is the most aggressive with ice accumulation Thursday night and early Friday. It is highly likely that these amounts are overdone; if this verified, this would be a crippling ice storm, and we are NOT expecting this:

feb20-microcastice

Precisioncast is more realistic with ice amounts, but still may be too aggressive:

feb20-adonisice

Forecast

I still think it is too early to make a specific, county-by-county ice accumulation forecast, but the threat for a widespread, light glaze Thursday night and early Friday is rising. A 1/4″ of ice usually causes power lines to sag or fall completely to the ground; I’m not ready to commit to the possibility of this happening anywhere in the Tri-State yet. Given the lack of consensus in model data, I will not release a specific ice accumulation forecast. Regardless of how much ice falls, it is important to know that roads may be slick and that elevated, cold, outdoor surface may have a coating of ice by late Thursday night.

I may do a video update late tonight, depending on how much time I can find tonight. I will update this blog tomorrow.