weatherbo Posted February 13, 2019 Share Posted February 13, 2019 41 minutes ago, Stebo said: What deck It wasn't that long ago that you had very little on the ground too. Crazy. haha! I've had 20" or more on otg for a couple months now, and 3' or so for several weeks. Last few pics for this event and eyes turn towards sniffing out the next snow! window where I took the pic of my snow stick last night that read 44". You can see it trying to poke back out as the snow settles Link to comment Share on other sites More sharing options...
Chicago Storm Posted February 13, 2019 Share Posted February 13, 2019 Finished with 0.44" ice accrual and 2.1" snow at ORD. Finished with 0.35" ice accrual and 1.5" snow here. Link to comment Share on other sites More sharing options...
Hoosier Posted February 13, 2019 Share Posted February 13, 2019 As far as what occurred with LOT... It was a tough forecast, as those involving different precip types tend to be more challenging. The way they handled certain things was understandable, but the way they handled other things was more of a head scratcher. The initial lack of a warning for ice falls into the understandable category. There were some indications that there could be maybe close to a quarter inch of ice somewhere (especially given mostly light to moderate precip rates and drops that weren't excessively warm), perhaps around I-88 and/or I-80, but that is borderline for a warning and exact placement was a bit questionable. As Monday wore on and it was becoming apparent that temps weren't responding much with the clouds and cool ENE flow, they could have been quicker to issue an advisory farther south in the cwa... Kankakee county, etc, particularly since the threshold for issuing one for ice is very low given the outsized impacts that the most minor glazes can have. Also as Monday went on, the short range models like the HRRR/RAP were hitting on a corridor of .25"+ ice potential. But as has been mentioned, those models underestimated the northward extent of the warm nose aloft. One could argue that perhaps there should have been an afternoon issuance of the ice storm warning for the I-80 corridor, but the majority of the data didn't support one much farther north at that point and I don't view this aspect as being as much of a botch as the lack of an advisory farther south. As afternoon turned to evening and it was apparent that the warm nose aloft had gotten farther north, I think it is fair to say that there could have been a quicker reaction to convert to an ice storm warning... at least for I-80 at this point if not farther north. I'm not really sure what held them back... perhaps they were concerned about temps warming up more quickly toward I-80 and some snow/sleet mixing in at times farther north (per HRRR/RAP) to hold ice accretion under warning criteria. Overall, it was not the finest forecasting performance by LOT. Forecast evaluations happen and they are aware of how they did. Criticism of NWS and other mets is okay but I think it should always be presented in a tactful way. I am not singling out anybody in particular because there are other NWS offices and mets who get called out here. We are fortunate to have professional contributions here, in particular from NWS mets like RC who can offer insight into what we see in those forecasts. Link to comment Share on other sites More sharing options...
RCNYILWX Posted February 13, 2019 Share Posted February 13, 2019 As far as what occurred with LOT... It was a tough forecast, as those involving different precip types tend to be more challenging. The way they handled certain things was understandable, but the way they handled other things was more of a head scratcher. The initial lack of a warning for ice falls into the understandable category. There were some indications that there could be maybe close to a quarter inch of ice somewhere (especially given mostly light to moderate precip rates and drops that weren't excessively warm), perhaps around I-88 and/or I-80, but that is borderline for a warning and exact placement was a bit questionable. As Monday wore on and it was becoming apparent that temps weren't responding much with the clouds and cool ENE flow, they could have been quicker to issue an advisory farther south in the cwa... Kankakee county, etc, particularly since the threshold for issuing one for ice is very low given the outsized impacts that the most minor glazes can have. Also as Monday went on, the short range models like the HRRR/RAP were hitting on a corridor of .25"+ ice potential. But as has been mentioned, those models underestimated the northward extent of the warm nose aloft. One could argue that perhaps there should have been an afternoon issuance of the ice storm warning for the I-80 corridor, but the majority of the data didn't support one much farther north at that point and I don't view this aspect as being as much of a botch as the lack of an advisory farther south. As afternoon turned to evening and it was apparent that the warm nose aloft had gotten farther north, I think it is fair to say that there could have been a quicker reaction to convert to an ice storm warning... at least for I-80 at this point if not farther north. I'm not really sure what held them back... perhaps they were concerned about temps warming up more quickly toward I-80 and some snow/sleet mixing in at times farther north (per HRRR/RAP) to hold ice accretion under warning criteria. Overall, it was not the finest forecasting performance by LOT. Forecast evaluations happen and they are aware of how they did. Criticism of NWS and other mets is okay but I think it should always be presented in a tactful way. I am not singling out anybody in particular because there are other NWS offices and mets who get called out here. We are fortunate to have professional contributions here, in particular from NWS mets like RC who can offer insight into what we see in those forecasts. Very good assessment. I think a big challenge in these situations other than making the assumption that the warm nose push will be at least as aggressive as the most aggressive model (NAM) is that we don't have any real time analysis of the warm layer. Aircraft soundings help but they're essentially point based so you can't track the trends and most of the soundings are from the larger airports. When the RAP/HRRR is underdoing the northward push and magnitude of the warm layer, it's a big hindrance. That's because the closest we have to real time analysis is the SPC mesoanalysis using the RAP as a background field, so it can definitely throw off even the best forecasters, and played a role in the lack of a lead time to warnings. As to the point about the southern CWA counties, the points you made are very fair. Being off duty for the event and an outside observer but certainly watching things closely, I think the signs were there that temps would mostly be AOB freezing for much longer than expected. Just by tracking the surface wet bulb zero line on mesoanalysis, it wasn't budging and didn't make any northward movement until the late evening. That would also play a role in reaching the warning criteria ice accums farther north. With the surface low well south and east-northeast winds locking in temps mostly 32 or less and pulling from dews in the low-mid 20s over southern lower MI and northeast IN, that argued for multiple hours of flatlining temps. In addition, the sensitivity of even a glaze of ice accums w.r.t. road conditions is something that most of the time we err on the side of caution for and issue an advisory. Certainly a very tough forecast and often times we do perform internal assessments about what went well and what could've been done better in cases like these. Sent from my SM-G965U using Tapatalk Link to comment Share on other sites More sharing options...
Jackstraw Posted February 13, 2019 Share Posted February 13, 2019 8 minutes ago, RCNYILWX said: I think a big challenge in these situations other than making the assumption that the warm nose push will be at least as aggressive as the most aggressive model (NAM) is that we don't have any real time analysis of the warm layer. This Link to comment Share on other sites More sharing options...
josh_4184 Posted February 14, 2019 Share Posted February 14, 2019 Picked up about 10" from the synoptic event, then another 10-12" of LES since early this morning, the lake guns really fired up way more then expected even with APX who was caught off guard. Total snowfall the past two days about 22". Have about 34" OTG atm after settling. Link to comment Share on other sites More sharing options...
thomp2mp Posted February 14, 2019 Share Posted February 14, 2019 Got decent accums this morning from LES, did as best as I could to measure it, and approximated 3.5" here pictured patio table had barely anything on it last night Link to comment Share on other sites More sharing options...
RogueWaves Posted February 14, 2019 Share Posted February 14, 2019 12 hours ago, beavis1729 said: Congrats Bo!! Incredible stuff. You should become a COOP observer for the NWS. You may set all kinds of snow records for MI. I think MQT's record depth is 63" in March 1990; not sure about the MI state record. Ok, back to my self-imposed exile. 117" somewhere in the Keweenaw and not in recent times iirc Link to comment Share on other sites More sharing options...
RogueWaves Posted February 14, 2019 Share Posted February 14, 2019 Backside over-performed for SWMI and took mby to a 6.5" total. Better than any snowfall map I glimpsed by any model. So, while the front-end was a big let down, over all I'm pleased with the outcome here. Link to comment Share on other sites More sharing options...
michsnowfreak Posted February 14, 2019 Share Posted February 14, 2019 Got home from the amazing scenery of the upper peninsula, and everything was still encased in ice. Picked up 0.62" precip, mostly freezing rain per my gauge, then about 1.8" of backside snow which blew and drifted everywhere. With the warmth today, most has melted. Link to comment Share on other sites More sharing options...
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