BLOG: Here Comes Winter!

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As you know if you have seen my Winter Forecast , we are expecting another colder-than-average Winter across our part of the country. It would be nice to have an unusually mild November before we settle into another long Winter, right??? Well, if only wishing made it so.Next week will bring some January-like cold into the United States. I GUARANTEE you will hear all sorts of talk about the "Polar Vortex" again....it was last year's buzzword after all. As a quick reminder, the Polar Vortex is NOT something unusual...in fact it exists almost year-round. Occasionally, every single Winter, it roams away from it's usual home around the North Pole and has a part in changing weather regimes around the Northern Hemisphere. Today, it's in it's "usual" spot (highlighted in black): vorrtexA sequence of events will take place in the coming days that will dislodge the vortex and send it south. Would you believe that a key player in our cold next week is a Typhoon that is SE of Japan right now??? Typhoon Nuri is "recurving"  in the western Pacific right now and is shown ("L" on left) on this analysis of the sea level pressure in that part of the world: slpnowThe system will rocket northeast and EXPLODE into a very intense low pressure system in the Bering Sea by this weekend: slpsaturdayLook at all those isobars! This storm will cause enormous waves and a tremendous amount of wind. But I promised to show you what this system has to do with our upcoming cold snap. This system, as most "recurving" typhoons do, will cause an atmospheric chain reaction in the Pacific and over North America. It's important to remember that air is a (invisible) fluid. It behaves very much like water. The intense system west of Alaska is like a big rock that is dropped in a pond. Downstream of that rock, a big wave forms. In the atmosphere, we refer the top of the wave as a ridge. That ridge can be seen pumping up in western Alaska on Saturday: jetsaturdayNote there is already a pre-existing ridge on the West Coast of the US and over NW Canada.By the middle of next week, the jet stream will look like this: jettuesA massive ridge of high pressure on the West Coast, extending all the way up to the Arctic Circle....and our "friend" the Polar Vortex has dipped all the way to far southern Canada. So, to review, the recurving Typhoon pumped the ridge, which in turned deepened the trough over North America.The air that will enter the US will come straight from the North Pole. Here's a look at the temperatures and steering currents a week from now: 500andtempswedsTemperature color table is on the left.Ok, so that's a lot of "big picture" stuff. What's about the weather here in Ohio/PA??This pattern will likely produce a few days late next week where highs stay in the 30s. Latest GFS Ensemble model temperatures for next 16 days: gefsYikes.Depending on how long this pattern persists, we might have a shot to crack the top 10 coldest Novembers on record in Youngstown. Here's the list, based on average temperature (combining highs and lows):coldnovembers 1976 tops the list and that's interesting because the Winter of 1976-1977 (the coldest on record in Youngstown) is one of our "analogs"...ie years in which the oceans and atmosphere have conditions most similar to this one. See the Winter Forecast video for more on "analogs".What about snow??? I don't think accumulating snow  will accompany this shot of cold in the WFMJ viewing area, although flurries will surely be seen. Lake-effect snow WILL be an issue along I-90 in NE Ohio and into NW PA and western NY. Enough to shovel: eurosnowThanks for reading!Eric  

BLOG: Wild Week of Weather Ahead

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Good Monday to you!It's been a while since I have done a true "Blog" post, as the weather in September and October has a tendency to be "boring". Well the weather will be far from boring this week.First, the big changes that will occur in the near term. It was a cold and frosty start today with low temperatures in the 20s in spots: lowsThis afternoon will be gorgeous once again with a nice warm up as well. A warm front is knocking on the door: currentsfc In the wake of that warm front, Tuesday morning will start as much as 30 degrees warmer than this morning did and we should have no trouble getting into the lower and perhaps middle 70s in the afternoon. BUT, that cold front you see on today's weather map?...It will head our way in the afternoon. Showers will become likely after 2-3pm. Here's the 2pm Tuesday simulated radar on the NAM4 model: 2pmtuesAhead of the front, it will be a pretty moist and unstable air mass. Check out the dewpoints getting into the lower 60s...pretty impressive for late October: tuesdaydewThese relatively high dewpoints will provide some of the "fuel" for showers and even thunderstorms. The instability is not "through the roof" but it's pretty decent. CAPE (convective available potential energy) will be 500-1000 which is certainly enough to support thunder: cape There is an outside chance any thunderstorm produces "severe" wind gusts. Remember, the definition of a "severe" thunderstorm is a storm that produces 1) Hail 1" or larger and/or 2) wind gust of 58 mph or greater. At 5000 feet in the air, wind speeds will be as high as 60-70 mph so a decent storm with a strong downdraft could pull down some of that wind: 850winds The winds and energy at jet stream level (around 30,000 feet) will be strongest to our west so the setup is not "great" for severe weather: jetThat is why the Storm Prediction Center just has us in the "Marginal" risk category: day2 After the passage of the cold front, Wednesday and Thursday will be cooler and more tranquil days. Then, a STRONG shot of cold air is heading our way for Halloween. How cold? There will likely be flurries and snow showers seen around the region by Friday evening! gfsfrieveI would not expect this to stick, except perhaps a dusting on a few non-paved surfaces. Flurries may even be around into parts of Saturday. BRRRR!The cold shot is a quick hitter. After a chilly weekend, we should be back to average and perhaps above average readings for the first work week of November: gefsAnd OVERALL, this is not likely to be a cold pattern during the first 10 days or 2 weeks of November. Here's the CFS model outlook for the 2ns week of the month: cfsnov813Lots of warm air across the continent. So, while there will surely be cries of "Winter is starting already!" Friday and Saturday, as a reader of this blog...you will know better. :)Speaking of Winter, a reminder....this folder on my desktop will be opened up and we will reveal our Winter 2014-2015 forecast on air and ONLINE this Thursday, October 30! WINTER!Thanks for reading.Eric