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Saturday, December 11

STORM UPDATE/TIMELINE

Nothing fancy here, just outlining the basics and headlines of this storm over the next few days now that we can narrow down a few things:

1.Rain arrives 5-9AM Sunday, with earlier arrival southwest of Rochester moving northeast throughout that time period. I expect a healthy dose of rain off the bat(with a minimal chance for brief periods of sleet), with lingering showers or steady light-moderate rainfall through the daylight hours.

2. I'm pretty convinced on this dry slot. Look at the storm right now and it's crystal clear. It's a well-wrapped system, and storms on this path typically give us that several hour break in the action. I expect us to quiet down from about 5-6PM Sunday through the 2-4AM timeframe Monday morning.

3. Because of the dry slot, there probably won't be much in the way of a rain/snow mix. It happens to time out so that the rain dies as it cools and then the snow starts to fly after we're well below freezing.

4. I expect the heaviest of the snow to fall later Monday through Tuesday based on lake effect parameters. I still have to see how the winds align behind the synoptic storm, but lets just say that it's not quite as well aligned with the upper lakes as the last storm. Winds are also still projected to be at a decent speed Monday and Tuesday, so blowing snow is still a concern. Windchill values have several opportunities to fall below zero during the colder parts of the day (very early, very late) Mon-Wed.

5. There WILL be areas that get a good helping of snow (around or even above a foot) but this storms lake effect activity won't be as long lasting as before. Those hardest hit spots will likely be east of Rochester in Wayne county come Tuesday as the winds align more WNW and grab moisture from upstream lakes.

Hope that's enough to whet your appetites until tomorrow!

56 comments:

  1. I'm looking forward to Monday and Tuesday

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  2. Do you anticipate the NWS will eventually issue a Lake Effect Snow Watch for our area? Or do you see it to be un-impressive enough to probably not warrant any headlines?

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  3. By the way, when I say "our area" I mean the immediate Rochester area (Monroe county).

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  4. I have to respectfully disagree on several points. I don't see Wayne county being the target over Monroe county because I see the winds being more NW'erly than WNW. In these cases, I wouldn't be surprised to see a persistent band coming onshore right across Monroe county. I also think that you're cutting the duration too short. Latest NAM and other guidance indicates that good moisture and bitterly cold cyclonic, NW flow will last through Wednesday. And lastly, with all of that said, I think that you are being a bit too conservative on the totals. 15 to 25 inches seems to be closer to reality given all that I have noted above. But this is just my two cents, for whatever that's really worth.

    I also expect Watches to be issued by tomorrow afternoon for Monroe county (possibly even Orleans and Niagara this time aroun). And that would further show that Wayne county won't exactly be the target this time around.

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  5. Even with a NW target Wayne county would still be a focal point. During any lake event from WNW to NE Wayne county usually has more snow then Monroe County. If you look at the last event which featured a vast majority of the time with NW winds places in Wayne county got 30-45 inches of snow (Newark had 42 inches). With a NW flow of air Wayne would still get hit hard.

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  6. You also have to look that there will be less moisture available in this storm then the last storm. I just do not see those 2-4 feet snow totals as we saw last time.

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  7. No doubt Wayne county will get hit hard by this event. I just believe that Monroe county will do very well on this event. Possibly as well as the last event with 20" was common from the city north. There will be A LOT of upstream moisture. No, there won't be the excellent connection from the upper lakes, but lake Ontario will produce copious amounts of snow from Lockport all the way to Fulton. But yes, Chris, I think Ontario will do VERY well. Hope you're ready to do lots of shoveling.

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  8. ***correction - Charles, not Chris. Sorry I got you're name wrong.

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  9. Example:

    This is the NAM's projection of 7AM Wednesday. I hardly think the lake effect will mostly end by Tuesday given the well defined streamers still going in full force under a very cold, regime early Wednesday. Also, consider history of the last event. The NWS ultimately extended Warnings all the way until Thursday, nearly a day and a half longer than initially projected. Models, if anything, are underestimated this event.

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  10. Here's the link I referenced above as the example:

    http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/nam/00/images/nam_pcp_084m.gif

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  11. I have no doubt that snow may stick around into Wednesday... I think that Scott has not talked about Wednesday because it is too far out. That is still days away from us... It depends on the connection to the bay if it forms then just like this last event we will get heavier then forecasted snow amounts but if it does not connect then it will be hard to get a long period of heavy snow like last event

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  12. Also, here's the total precip through early Wednesday based on the NAM. It is projecting up to 0.50" of liquid precip (which is very likely underestimated). When you consider the snow to liquid ratio of this event given the very cold temperatures, coupled with it being underestimated, you're talking about major snow totals. Also notice it taking the heaviest totals all along the south shore in an almost NNW direction.

    Again, this is just my two cents. I could be wrong....wouldn't be the first time, and definitely wouldn't be the last.

    http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/nam/00/images/nam_p48_084m.gif

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  13. This is WEDNESDAY afternoon per the very latest GFS data that is streaming in. As you can see, there is still good moisture and cyclonic flow pouring off lake Ontario right through the day Wednesday. I'm tellin ya...Lake Ontario is going to really flex its muscles on this one just fine without the help of Georgian Bay. And it will be just as long duration as the last event. Not shorter...

    http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/00/images/gfs_pcp_090m.gif

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  14. One final note...and then it's time to get some zzzz's.

    Both the GFS and the NAM have upped their total liquid precip projection for the period from Monday through Wednesday. Both also have good moisture pouring in right through Wednesday afternoon, at least. Previously, they were trying to push the sufficient moisture out earlier. These models are to be taken seriously at this juncture because we are now within the 90 hour timeframe. The latest trends merely indicate that they are finally grasping the magnitude of lake effect that was previously being missed. And they are probably still underestimating to some extend, even at this point.

    Again, this is all in fun. I'm just respectfully disagreeing on a few points. I could be wrong. Feel free to disagree and fire away at me if you wish. It's all in fun debate and discussion.

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  15. You know it's funny. I've been forecasting lake effect to stick around through Thursday. Why does anyone suspect otherwise? Here's the deal in my view as I head off to bed. NAM is best in these scenarios and was great last week. Given the airmass, moisture and depth of cold air, this will be another 3 day lake effect event.

    I will take the same road I always do and forecast snow daily. Lake snow watches will be issued soon and probably for all counties along I-90.

    As Bob has said, significant snow can be expected again. I do think Monroe, Wayne, Genesee and Orleans will get decent snows depending on where you are. If you got it last week, you probably will again.

    Good night!

    Scott

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  16. And again, I really don't mean any disrespect. I love this blog and the news 8 Weather team. If I have stepped over the line with my thoughts I apologize and will refrain.

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  17. In the last event the primaty wind was wnw not NW. I beleive this is why Wayne county saw the best snowfall. I beleive a nw wind would give MOnroe and Wayne counties a good chance of significant snow.Did anyone notice that the NWS out of Buffalo is calling out metro Rochester several times with this event coming up. They have never done that before. Very interesting. They also state the watches for us shoould be issued by tomorrow afternoon. We will see. We lost a lot of snow today and will lose a lot tomorrow so hopefully we will get it all back.

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  18. Some keeping saying there will not be a Georgian Bay connection, Why not? The winds will be NW.

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  19. NWS has issued a LES watch until Wednesday morning. Not sure what areas will get the most snow?

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  20. I think there will be a connection but just not for the entire event like there was last time

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  21. Charles do you places like Fairport and Pittsford getting heavy LES?

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  22. Who cares what Charles thinks? I thought this is the News 8 weather forum.

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  23. OK News 8 do you the Fairport/Pittsford towns will get heavy LES?

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  24. Yes you will over an extended period of time thru wednesday.

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  25. Eastern burbs of Monroe should expect near 12" + by the time it all winds down. Cold also should stick around to insure a while Christmas for those who get lake effect this week. Once again though I think NWS is neglecting Orleans county

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  26. Why is the rain dieing south of us? Is the dry slot earlier than expectet?

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  27. Yes, I agree. Places like Albion north to the lake should do very well with this in Orleans county. Again, I really don't know why they neglect those folks out there. I don't know if it's becuase they figure it's not populated enough to worry about or what. But, in the end, I suspect Orleans county will be issued an Advisory at some point. I hope anyway. If Tom Niziol reads this blog, i'd be interested to hear from him on why so many 6+ inch events have gone by without a single headline for Orleans county....

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  28. The NWS has a whopping 6-12 for us. No big deal. 6-12 of fluff is like 2-5 of real snow.

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  29. Why are the counties bordering lake eri under a Winter Storm Warning already and our is just a lake effect snow watch. WHat is the difference between a lake effect snow warning and a Winter Storm Warning. We are supposed to receive 6-12 and they are supposed to recieve 8-12. I do not see the difference.

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  30. Does anyone know what the 10:30 GFS run says?

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  31. !!! New Lake effect snow watch !!! now 12-18" instead of 6-12"!

    New GFS run nothing really new... Cold and a some lake effect at times... no new storms.

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  32. Not sure where you 12-18 from?

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  33. How about us west side suburbs? Especially those by the lake, like Hilton? Will we get bypassed or will we see some of those flakes? Thanks!

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  34. The rain has begun to change over to snow over Ontario, CA

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  35. NWS has Monroe CTY east to Oswego under 10-16" up from 6-12" this am

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  36. ONTARIO, CA??????????????????? THE NWS CHANGES THEIR FORECAST MORE THAN ANYONE I HAVE EVER SEEN. NEXT HOUR IT WILL SOMETHING DIFFERENT.

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  37. Charles- how much snow Rochester going to get in December total or is this lake effect going to be the last "big snow of December"?

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  38. Why are people asking Charles? Scott, Brian and Bob are the meteorologists on this blog. If you have a question, ask them.

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  39. we can ask who ever we want it doesn't matter....

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  40. This comment has been removed by the author.

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  41. I am not planning on giving any forecast on here

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  42. Nice East coast BOMB on the Euro

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  43. What does that mean SARWx nice East coast BOMB on the Euro?

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  44. It would be a very strong storm ... it does not mean that we will get it

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  45. Yeah like this storm people predicting 7 days in advance!

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  46. I'll ask the same question M in Hilton did: What about Greece and Hilton? We sit about 2 miles from the lake. News 8 can you answer? Looking out my window right now it looks like fog....or maybe everyones running their dryer.

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  47. Fog is forming. That is what you are seeing. As for the forecast, no one can or should try to predict beyond 5-7 days. We can only see trends beyond that. So whenever a long range model bombs a storm 7-10 days out, not really worth a discussion. Bobby will publish an update on the snow soon with our forecasted amounts soon

    Scott

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  48. What happend to all the rain we were supposed to receive. We hardly received a drop in Gananda. I am glad, but this so called storm even underperformed in rain.

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  49. CHANNEL 10 IS STATING THAT THE HEAVY LAKE SNOW WILL BE CONFINED TO THE ROUTE 104 COORIDOR FROM ROCHESTER EAST. I DISAGREE.

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  50. Even the over hyped accuweather does not have the city of Rochester getting big lake effect. LES will be another non event for most like the Big Monster Storm was!

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  51. Yes, you can ask whoever you want about the forecast...but if you want an EXPERT answer, I would advise asking the actual experts....Scott, Brian and Bob. Anything else is just what we in the business call "toy forecasting."

    No offense to Charles, he's a very smart and ambitious student of weather. He may one day be a meteorologist...but not yet.

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  52. Why is this Charles dude posting a forecast? I get my weather from the most accurate team around. Hetsko and the boys are spot on, much like my Friday Forecast for the Bills. Mark it Downnnn! I am 10-3 on the season! Batten down the hatches for some wintry weather the next few days. Of course I fly out for Miami Friday for the Bills next game....lol

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