March 4-6 Winter Storm

[Geos]

About 10" and counting for DLL at 66hr.

 

...12-14" by 72 hours.

[michsnowfreak]

Proper measuring is checking (and clearing) the board at 7 AM, 1 PM, 7 PM, and 1 AM. That's the probable reason for the 4" Midway snowfall.

 

However, anything that falls and melts in between is not counted. Most people check as soon as the snow lets up and reports it, thus higher amounts than the 'official' measurement. That really makes ORD/Harwood Heights measurements seem strange.

A snowfall like the last one is quite rare, so it made the measuring quite tricky. That is definitely true about the measuring times. However...say you cleared the board at 1pm, and then 3 more hours of snow dropped 1.5" when the snow let up at 4pm but if you waited til 7pm (after 3 hours of no snow) and the snow had settled to 1.3". You would not have to wait til 7pm, if you are sure the snow is done at 4pm you could report then.

[MidwestChaser]

18z NAM LOL

[ILSNOW]

18z NAM LOL

baes off the 18z Nam should rename this the ALEK storm (12-14 for him)

[MidwestChaser]

[michsnowfreak]

Nice to see a slow north trend continue on the nam..keep coming north

[Hoosier]

High LAF crew meltdown potential if the 18z NAM is on the right track. Warm air is probably my biggest concern at this point. Nonetheless, locally speaking it's one of the better potentials to get within 3 days this winter (that's not saying much).

[Geos]

If something like this verifies, I might have to start putting snow in the backyard. Don't have much more room out front within 12 feet of the driveway! lol

[BeastFromTheEast]

Gotta love the fracking nam, farther north, weaker than the globals lol.

lolwut? 

Nam is going bonkers with the QPF compared to other models.. 

[BeastFromTheEast]

Going to be an incredible razor thin cutoff up North here.. 

[Brewers]

Going to be an incredible razor thin cutoff up North here.. 

 

Yup we're living on the edge

[Geos]

18z NAM vs. 12z GFS.

 

Both models have 12"+

 

[gosaints]

Saints-

 

Looks like we are shoveling...spring cancel

Yes this is the type of storm that could really produce la crosse going watches west of the river

[Thundersnow12]

What a run. Wonder if the NAM would handle the banding better.

[Indystorm]

Even if we halve NAM precip this would certainly still be the best storm of the season here in Michiana.  LAF may have to worry about mixing or ice given prior analog mentioned earlier.  Tracks can still change, however.

[A-L-E-K]

lol

[MidwestChaser]

Even if we halve NAM precip this would certainly still be the best storm of the season here in Michiana.  LAF may have to worry about mixing or ice given prior analog mentioned earlier.  Tracks can still change, however.

 

Poor LAF. Nothing works out for those guys.   

[Brewers]

MKE SREF plume

 

Mean - 4.17

 

16.78

11.73

9.88

8.56

7.38

7.19

5.16

4.41

4.27

2.45

2.32

1.78

1.14

1.03

0.88

0.82

0.50

0.41

0.36

0.31

0.24

0.00

[Ajdos]

Nice to see a slow north trend continue on the nam..keep coming north

+10...

[ILSNOW]

The ALEK storm

 

Dvn update

 

INITIALLY THERE WILL BE A WARM ADVECTION WING OF MODERATE TO
POTENTIALLY HEAVY SNOW DEVELOPING BY EARLY MONDAY WHICH WILL THEN
PIVOT NORTHWARD AND SET UP SHOP OVER OUR NORTHERN CWA DURING THE
DAY. IN MARCH YOU HAVE TO START GETTING CONCERNED WITH THUNDERSNOWS
IF THE ADVECTION IS INTENSE ENOUGH. THIS WILL BE SOMETHING TO
MONITOR. THEN THE MAIN DYNAMICS WITH STRONG LARGE SCALE FORCING AND
DECENT MOISTURE ARRIVE MONDAY NIGHT WITH THE DEFORMATION ZONE THEN
FORMING OVER MOST OF THE CWA ON TUESDAY LASTING INTO TUESDAY NIGHT.

SNOWFALL AMOUNTS OF AT LEAST 4 TO 10 INCHES SEEM LIKELY WITH THE
HIGHEST AMOUNTS ACROSS OUR NORTH HALF. HOWEVER...THIS IS A COMPLEX
SYSTEM AND DETERMINING THE EXACT LOCATION OF THE HEAVIER SNOW BANDS
IS RATHER DIFFICULT AT THIS POINT. ALSO THE TRACK OF THE SYSTEM IS
NOT ETCHED IN STONE YET. THERE MAY ALSO BE EMBEDDED THUNDER MONDAY
NIGHT WITH THE STRONG DYNAMICS WHICH MAY ENHANCE SNOWFALL TOTALS
EVEN MORE. THE GRADIENT TIGHTENS TUESDAY EVENING AS THE SURFACE LOW
PUSHES OFF TO OUR EAST. WIND GUSTS SHOULD INCREASE TO AT LEAST 30
MPH WHICH MAY PRODUCE SOME BLOWING AND DRIFTING.
 

[Geos]

LSE and DMX just hoisted watches.

[Brewers]

LSE and DMX just hoisted watches.

 

You can add DVN as well.

[MidwestChaser]

http://www.meteor.iastate.edu/~ckarsten/cobb/cobb.php?model=namm&site=kdpa

[BeastFromTheEast]

Mad-Town probably will be 60"+ after this storm..

[TugHillMatt]

Nice to see a slow north trend continue on the nam..keep coming north

 

I agree. But then Indiana has been denied alot this year. My area also has a one foot deep glacier that is giving the early March sunshine quite the fight. Not melting much at all..

[Geos]

15z SREF plume is averaging 14" for DBQ. About 10-14" for DLL and go saints.

[Natester]

Well it can be save to say that piles of snow will linger well into April after this storm.  There are still piles of snow left from the December 19-20, 2012 blizzard.

[TugHillMatt]

Going to be an incredible razor thin cutoff up North here.. 

 

What else is new??? Doesn't the NAM always do that? Plus, razor sharp cutoffs seem to be the "new normal".

[Hoosier]

18z NAM text output for LAF...lol.

03/05 06Z   32     31      94      14    0.07  0.00    541    550    1.9 -21.0 1011 100 -RA   010OVC227    0.0    6.2
03/05 09Z   32     31      91      13    0.09  0.00    542    549    2.8 -21.4 1008 100 -RA   011OVC238    0.0    6.8
03/05 12Z   32     31      95      11    0.10  0.00    541    547    1.9 -22.2 1007 100 -RA   008OVC192    0.0    4.5
03/05 15Z   33     32     101       5    0.13  0.00    539    545   -1.6 -22.9 1007 100 SN    007OVC233    1.4    0.8
03/05 18Z   33     32       8       4    0.21  0.00    535    540   -4.4 -24.1 1006 100 -SN   007OVC239    2.1    2.7
03/05 21Z   33     30     347       9    0.03  0.00    531    537   -7.2 -26.0 1007 100 -SN   008OVC193    0.3    4.8

[RCNYILWX]

Proper measuring is checking (and clearing) the board at 7 AM, 1 PM, 7 PM, and 1 AM. That's the probable reason for the 4" Midway snowfall.

However, anything that falls and melts in between is not counted. Most people check as soon as the snow lets up and reports it, thus higher amounts than the 'official' measurement. That really makes ORD/Harwood Heights measurements seem strange.

It's all tied to GMT synoptic hours (12z, 18z, 00z, 06z), so in CST, you measure at 6am, 12pm, 6pm, and 12am, but you're right about EST. On the second point, you're actually supposed to measure when the snow stops and not wait until the synoptic hour. You're only supposed to wait until the synoptic hour while it's still snowing, to account for compaction. Let's say it quickly snowed 1" in a very marginal temp situation after 18z and then it stopped. If you wait until 00z and the snow melted by then, it would be like the snow never fell, which is obviously incorrect.

The ORD measurement was decent for the last event, best we could tell. It was lower by a bit over an inch than CoCoRaHS reports close by in Elk Grove Village. Harwood Heights was probably wrong: IL-CK-196 : HARWOOD HEIGHTS 1.9 NNE * : 0.93 / 3.4 / MM / MM- ratios were low but not 3:1. It's a double-edged sword with snowfall measurements for the WFO's because obviously there's a right way to do measurements, but if everyone did it that way, we wouldn't know how much snow was falling real time for purposes of verifying warnings or needing to upgrade advisories to warnings.

Another point is that the measurements that are done more frequently than synoptic hours are probably a bit inflated, but on the other hand, the other measurements we rely on, from COOPs and some CoCoRaHS, are not any better, and likely underdone because other than the Midway 3SW COOP, they're only measuring and clearing the board every 24 hours (which may have been the case with Harwood Heights).