Thursday 10:30am

With one storm behind us, it looks like there is the chance for some more in front of us. This coming weekend will see two systems. The first looks unimpressive and will bring rain to us on Friday night and into Saturday. Some light snow might mix in with it, but accumulations will be next to nothing.

Later in the weekend looks to be tricky. Sunday and Monday will bring a rather impressive storm system into play. However the models are all over the place and go back and forth from snow to rain.

Here is the latest GFS for Sunday at 7pm. A nice band of heavy precip over the Ohio Valley area, but there are two problems with this. First, notice that the 540 thickness line is well to our north (the first blue line north of the Ohio River). This would essentially be the rain/snow changeover line. That 540 line doesn't go south of us until 95% or more of the precip is gone on Monday! So if that turns out to be the case, this will be an all rain event. This will definitely be something we'll need to watch closely.

Here's what the Louisville NWS says about this system:

BEST PRECIPITATION CHANCES SEEM TO BE ON TAP FOR SUNDAY AFTERNOON THROUGH
MONDAY.  GOING CLOSER TO THE 18/00Z EURO SOLUTION HERE...WOULD
RESULT IN PRECIPITATION BEING IN THE FORM OF RAIN DURING THE DAY ON
SUNDAY.  TEMPS LOOK TO STAY JUST WARM ENOUGH FOR MOSTLY RAIN ON
SUNDAY NIGHT ACROSS THE NORTH...BUT SOME SNOW COULD MIX IN AT
TIMES...WHILE THE SOUTH LOOKS TO STAY ALL RAIN.  PRECIPITATION WILL
CONTINUE INTO MONDAY WITH TEMPS COOLING FROM WEST TO EAST.  WE
TRENDED TEMPS HERE CLOSE TO THE RAW 2M TEMPS FROM THE 17/12Z AND
18/00Z EURO SOLNS.  LOWS SAT NIGHT SHOULD DROP INTO THE LOWER 30S
WITH HIGHS ON SUNDAY WARMING INTO THE UPPER 30S IN THE NORTH AND
LOWER 40S IN THE SOUTH.  LOWS SUNDAY NIGHT LOOK TO COOL BACK INTO
THE LOWER 30S IN THE NORTH AND MID-UPPER 30S IN THE SOUTH.  HIGHS
MONDAY WILL LIKELY TOP OUT EARLY IN THE DAY IN THE UPPER 30S TO THE
LOWER 40S BEFORE FALLING DURING THE AFTERNOON.

One other thing looks really good for this to be an almost all rain event. At left is the 850mb temps and you can see that the top red line goes over our area. That indicates 3 degrees celcius above freezing. The purple line is freezing and that is well north of us. This is also supportive of rain. The 850 temps really need to be below freezing for this to even be a wet snow because the 700-850mb region is typically where the snow forms. With this model run it looks like temps will be just too warm to support snow in our area.

Now this won't be the same for Indy. If you are heading toward Indy you will definitely see some snow accumulations. The latest QPF's from the HPC suggest over 0.5" liquid in the Indy area and with that being a more wet snow, they could get around 5" snow. Certainly a 3-5" forecast of snow for that area is not out of the question at this point. Now what if the Low decides to go further south? It is certainly possible and if it does that snow will be pulled down into our area. I'll update more on this system as the models come in again.

Mon 9:15pm

The low has now moved well into West Virginia, but still a few flurries and light snow showers in the area. Expecting about 1/2" or less overnight as these continue to move through.













The NWS has issued the following Special Weather Statement:

741 PM EST MON FEB 15 2010 /641 PM CST MON FEB 15 2010/

...LIGHT SNOW AND BLOWING SNOW CONTINUES OVER SOUTHERN INDIANA
AND CENTRAL KENTUCKY...

LIGHT SNOW WILL CONTINUE THROUGH THE EVENING HOURS OVER SOUTHERN INDIANA
AND CENTRAL KENTUCKY. AN ISOLATED MODERATE POCKETS OF SNOW MAY
MAKE AN BRIEF APPEARANCE THROUGH 930 PM EST. GENERALLY LESS THAN
ONE HALF INCH OF ADDITIONAL SNOW ACCUMULATION IS EXPECTED.

IN ADDITION...WESTERLY WINDS OF 10 TO 15 MPH WILL CONTINUE WITH
A FEW GUSTS TO 20 MPH WILL CAUSE SOME BLOWING AND DRIFTING OF
SNOW. DRIVERS SHOULD BEWARE OF SNOW RECOVERING SOME OF THE CLEARED
ROADS AND REDUCED VISIBILITIES BECAUSE OF THE BLOWING AND DRIFTING
SNOW. DRIVE CAUTIOUSLY!

Mon 4:45pm

Areas of new snow have developed over Illinois and this will continue to be the case throughout the evening. As the low on the Kentucky/West Virginia border moves off to our east at a fairly rapid pace, expect snow showers to develop in our area as wrap around moisture comes into our area again. At this point most of our accumulating snow is over. However it is possible for another 1-2" additional snow throughout the evening and overnight.

Mon 2:30pm

More snow in Huntingburg. With the flurries and snow showers in the past few hours, we're now up to about 8". More snow flurries in the area and this won't be the end of it as more is to come later tonight.

7 Day Forecast

Here is my updated Huntingburg Weather 7 Day Forecast.

Preliminary Snow Totals Map

Here is a graphical map of what has fallen so far. More will be added to most of these areas throughout the day as we get wrap around snow from that low. So far it looks like we were right on target with the snow forecast. You can really see that banding that set up just as the models predicted that it would.

Mon 10:30am

Here is an updated radar for 10:15am. Still quite a bit of snow out there. The snow over Dubois County is moving to the south because of where the H5 low is situated. See the map below for details. I'll be posting a snow totals graphic later this morning.

Mon 10am

Just measured 7" of snow in my backyard! That's up from 5" last hour. The snow is really coming down hard here as you can see by the radar at left. The green bands are the areas of snow with a high rate per hour.

Check out these pictures from my backyard! Let it snow!!! You can really see how fast the wind is whipping around by looking at the flag on my house.

Mon 9:30am Snow Totals

Snow totals are really ramping up over the area. Radar still showing heavy snow over much of Southern Indiana. A nice dry slot is moving into the area from Illinois and that might give us a break for a while, but expect more snow to develop this afternoon as we get wrap around snow from that upper level H5 low now situated just over the Ft. Knox area. Just as I had mentioned earlier, the low is tracking right along the Ohio River and that brings the heaviest snow totals just to the north of the low.

Here are some very preliminary reports I have found so far from the NWS and other blogs:

• Huntingburg (from me) 5"
• Taswell, IN 6.5"
• Mt. Carmel 7.5"
• Evansville 4.2"
• Newburgh 5"
• Rockport 6.1"
• Boonville area 7"
• Petersburg 4.1"
• Henderson 1.8"
• Princeton 5"
• Jeffersonville 4"
• French Lick 5"
• Scottsburg 6"
• New Albany 4.5"
• Salem 4.5"

I'll update more as the morning goes on.

Sun 8pm

Check out this radar image from 7:3opm Sunday evening. I've placed two Lows on the map as a visual. The first batch of snow associated with the surface low and cold front is now moving east out of Southern Indiana and into Eastern Kentucky. But check out the snow beginning to churn in Illinois. This is caused by the H5 low now situated over Missouri. This will be our major weather maker overnight. Expect heavy bands of snow at times as this low moves along and just south of the Ohio River overnight.


To get an idea of how deep this snow is, check out the Enhanced IR to the left. The coloring indicates cold cloud temperatures and shows the depth of this system moving in overnight. Compare that with the snow flurries over Kentucky from the surface low and you can see just how much the situation is going to change in our area in just a few hours.

I'll post an update again tomorrow morning. Be safe!

Sun 2:20pm

The NAM is now consistently running with a high precip zone along the Ohio River. Below at left notice the NAM from 00z last night with the NAM from 12z to the right. The dark blue band is a band between 0.5" and 0.74" of liquid precip. With snow ratios of nearly 20:1 coming with most of this later tonight, expect lots of accumulation in our area.



Notice also how the GFS is now back into agreement with the NAM. 00z from last night below left and 12z to the right. This is setting up to be a rock solid system, with probably the most snow we've seen around here all year.








The newest QPF from the HPC has downed the totals some from last night, but again 0.56 near Huntingburg isn't bad at all if you love snow! Everything seems to be agreeing with a narrow band of locally high precip in our area. This could be the one we've been waiting for!! I'll update again later tonight.

Update Sun 2pm

Winter Storm Warning now in effect for the Huntingburg area and most of the neighboring counties around the Ohio River. The storm really looks to be taking shape. At left is the visible satellite from 1:30pm today. You can see the H5 (500mb) upper level low spinning over the corner of Missouri, Nebraska and Kansas. The latest NAM places the track of this low right over the Ohio River as it passes through in the next 24 hours. This will put us in a prime location for a lot of snow.

At left is the 500mb analysis for 1pm today. You can see how the H5 low is closed and with intense vorticity. As this tracks right into our area overnight and through the day tomorrow, expect heavy bands of snow to set up in front of it.

Still looking like a solid 5-7+" for counties along the Ohio River is highly probable by the time this is all said and done Tuesday morning. Because of this, the HPC has continued to keep us in the 70% risk for at least 4" of snow.

Again for your reference: blue = 10%, green = 40% and red = 70%. Images below: left is prob of 4", center prob of 8" and far right prob of 12".

Winter Storm Watch Sun 4pm - Mon 7pm

Latest QPF maps from the HPC also shows increased moisture with this H5 closed low. The dark blue indicates greater than 0.5" liquid precip and the brighter blue greater than 0.75" liquid. This confirms that narrow banding we see so often with clipper systems.

From the NWS in INDIANAPOLIS:

VERY HIGH Q VECTOR DIVERGENCE OVER SOUTHERN CWA FROM TONIGHT INTO
MONDAY...WHICH CORRESPONDS TO STRONG ISENTROPIC LIFT AT LEVEL 285.
ALSO TROWAL EXPECTED TO BE OVER SAME AREA...AND AT 925 MB SEE BAND
OF RELATIVELY HIGH EQUIVALENT POTENTIAL TEMPERATURES ADVECTING IN.

TAKEN TOGETHER...THIS SUGGESTS RELATIVELY HEAVY SNOW WILL
FALL...ESPECIALLY WHERE TROWAL AND HIGH EQUIVALENT POTENTIAL
TEMPERATURES LINE UP. AS OFTEN WITH TROWALS...THIS BAND MAY BE
NARROW.

AVERAGE PRECIPITABLE WATER SOUTHERN CWA OVER THE PERIOD ABOUT THREE
TENTHS OF AN INCH...WHICH MORE OR LESS CORRESPONDS TO MODEL QPF. DUE
TO RELATIVELY COLD TEMPERATURES OVER AREA AGREE WITH BUFKIT WE MAY
SEE LIQUID SNOW RATIOS ON THE ORDER OF 20 TO ONE...

If Bufkit is right and we get a 20:1 ratio, that 0.84 precip around Louisville would mean 16.8" snow!! Bear in mind that not all of this will fall as a 20:1 ratio. That ratio will settle in as colder weather moves in with the H5 low after the surface low and associated cold front passes mid-day on Sunday. Still think that a good solid band of 5-7" with locally higher amounts over Dubois, Crawford, Pike and counties along that east-west line is a good call.

NWS in Louisville has issued a Winter Storm Watch for nearly all counties bordering the Ohio River. It appears as though a Winter Weather Advisory will likely be issued tomorrow or overnight. Might not also be surprised if that was even upgraded to a warning at some point.

EXPECT SNOW INTENSITY TO START PICKING UP LATER IN THE AFTERNOON...
THUS HAVE STARTED A WINTER WEATHER WATCH AT 4 PM SUNDAY. FOR AREAL
COVERAGE...HAVE THE HIGHEST TOTALS OVER THE NORTHERN TWO-THIRDS OF
THE CWA AND THUS THE PLACEMENT OF THE WATCH FOR ALL BUT THE SOUTHERN
TWO TIERS OF COUNTIES. THESE AREAS LIKELY WILL GET AN ADVISORY
ISSUED EITHER TONIGHT OR TOMORROW FOR SUNDAY NIGHT AND MONDAY.

Updated Snow Map

The latest 00z model runs from the NAM and GFS have started to take quite a varying path. Somebody is going to get some major snow! It's a question of who at this point. On the left you find the NAM and the GFS to the right. The dark blue indicates greater than 0.5" liquid precip. The NAM takes this right into the heart of our area, while the GFS has pushed it further north the past two model runs. Frankly it's a little late in the game to be pushing a system over 100 miles north of where it has been for several runs consistently. There could be many explanations for this, but it'll be interesting to see if the next runs due out later overnight track it back south again. I tend to believe the NAM is more reliable at this point.

Because of the updated last three model runs, I am going to have to up my snow totals. Models are all in agreement that somebody is going to get a heavy band of snow. The H5 low is now poised to go just south of Louisville and that would set us up in the perfect zone for the heavy snow. With a clipper system, the heaviest bands of snow usually occur just north of upper low. It would not be a shock to see some spots get greater than 7" with this system. A good swath of 3-5" still seems likely for much of the area.

Here is the latest 7 day forecast created by me on Sat 2/13/2010 at 6pm.

Major Winter Storm Valentine's Day

The latest model data shows a major winter storm from a strong Alberta Clipper moving into the region late Sunday evening lasting into Monday evening. A winter storm watch is now in effect for most of Southern Indiana and Kentucky from 4pm Sunday through 7pm Monday. The snow events will come in three waves, with the first beginning Saturday night into Sunday morning. Accumulations of 1-2" are possible. The main event will come Sunday afternoon into Monday morning with most of the snow coming from this time frame. Some wrap around moisture may come on Monday evening bringing another quick inch of accumulation.

At left is the latest probability from the HPC of at least 4" of snow. Prob of 8" is center and prob of 12" is far right.
Red = 70%
Green = 40%
Blue = 10%

With that said, here is my forecast graphic for what to expect. Going to go with generally 3-5" across our area, though locally higher amounts could easily be possible depending on how high the snow to liquid ratios become. With the first wave from the surface low tonight, a 10:1 ratio is probable. However ratios could be as high as 16:1 or even 20:1 as the cold, arctic air begins to set in behind the front. As of right now, the NAM is churning out 0.22" liquid and the GFS is at 0.36". The NAM seems to be underestimating the liquid as it has in some previous winter storms this year. I like the GFS much better. At at 20:1 ratio, that could mean as much as 7.2" and 5.76" at a 16:1 ratio! Because some of this will occur at the 10:1 to start, going with 3-5" generally across the area, but won't be surprised at locally higher amounts.