BLOG: April Review, May Preview

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April is in the books and wow did it end on a wet note. The rainy period over the last few days put Youngstown at close to 5" of rain for the month. Here's how this compares to average (also shown: the wettest April on record here in 1998): aprilcompareWe also recorded a little over 1" of snow in April.What about temperatures? For the month, it was actually a bit ABOVE average...the first time we have had a month on the "positive" side since December. Here's a look at the temperature anomalies across North America: aprilDespite the more tolerable weather in April, the first 1/3 of 2014 is still WAYYY below average in a large chunk of the continent: yeartodateSo let's talk about May. Although we are not gaining daylight as quickly as we did in March and April, the Sun is still getting higher in the sky and the days are getting longer. What the Sun is doing in May: sunmayThe strengthening Sun can lead to some hot weather in May. 90+ temperatures are not common, but not unheard of either. Here's a list of years with 90+ days in May: 90smayEspecially in the early part of May, we are still susceptible to cold Canadian air masses invading occasionally. It can get down well into the 20s on rare occasions: 20smaySnow? More than a "trace" is pretty rare:snowmay Be careful planting things too early. The next week is unlikely to bring subfreezing temperatures, but we can get a freeze as late as the 3rd week of May. Here's a list of years with subfreezing temperatures after May 15: freezesNotice last year is on the list.The average date of the last freeze of the season is roughly May 7-10 across the Valley: lastfreezeOk, enough about the past. What about the future? How's this May look? As you probably know, the Great Lakes are remarkably cold for this late in the season....with ice still found in the northern lakes. This is something we have to keep in mind; air masses that come out of Canada and across the lakes will get a little extra refrigeration this Spring and early Summer. That said, there should be enough warm air masses pushing in from the south and west to balance out those cool shots. Odds appear to favor a "typical" May in the temperature department. The average of the last week's worth of runs of the Climate Forecast System (CFS) model shows our region with an "average" or perhaps slightly below average look: cfsmayNOAA's outlook: noaamayIn the precipitation department, the CFS says "average": cfsmayprecipNOAA has a forecast showing higher odds for an above average month in the Ohio Valley:noaaprecip I will try and do an outlook for the Summer later this month. As always, thanks for reading!!Eric  

Tuesday Morning Severe Weather Threat Analysis

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Good morning all,Here's a quick update on the threat for severe weather across northeast Ohio and western Pennsylvania. First off, here's the video that goes along with this update:https://www.youtube.com/watch?v=mECoZK8nA8kIf you are at work and can't watch the video or are more of a reader, here's the skinny:You are no doubt aware that the southern US is in the middle of a nasty tornado outbreak, all thanks to a slow-moving weather system that has gotten itself stuck in the Midwest. Here's this morning's radar, satellite and surface analysis: sfcGenerally speaking, the zone between the warm front and cold front is where we will be watching for more ugly storms today.  The big question is: how far east does the warm front get? Anyone east of the warm front is likely to be in stable, rain-cooled air and will not have a very high chance of seeing strong or severe storms.The Storm Prediction Center's outlook for today has Ohio in the "Slight" risk, including these odds for seeing a damaging wind gust: windAnyone in the yellow area has a 15% chance of a damaging wind gust somewhere within 25 miles of a location. The odds of large hail are similar: hailThe tornado odds are very low in eastern Ohio and 2% in central and western areas: torCAPE is a measure of instability in the atmosphere, and those values will certainly be higher west of Youngstown this afternoon: capeWhile instability is lacking, there is a fair amount of "wind shear" in the area today. Wind shear is the change in wind direction and/or speed as you go up in the atmosphere. High wind shear can aid in the formation of hail and tornadoes. BUT, you need instability to get the air to rise high enough for those things to occur. I have overlain the wind direction at the surface (generally SE) with the wind direction at 5,000 feet (generally SSW) this afternoon: windarrows Bottom line: I think odds favor the WFMJ viewing area staying in the more stable sector this afternoon and evening, resulting in a very low chance of severe weather. There may be a thundershower in spots.As always, stay tuned on social media as I will be updating things all day as needed. Thanks for reading!Eric

BLOG: Despite Teases, True Spring in Hiding

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We have certainly had some nice Spring days so far this April, including the few days that preceded today.  After a long Winter, we have deserved each and every one of them! Check out the temperature anomalies for April so far...colors we have not seen here in a long time! aprilBUT....there are ominous signs that consistent Spring warmth is still a ways off for us.First of all, in the very near term, YES you might see a flurry/snow shower very late tonight and early Wednesday. Best chance in the WFMJ viewing area is probably in Mercer and Trumbull counties. Check out the latest simulated radar on the HRRR model for daybreak Wednesday: hrrr_ref_cleveland_14One of the big reasons we have to be on guard for cooler-than-average weather this Spring is the VERY cold, and still somewhat icy Great Lakes. The ice cover this late in the season is pretty remarkable. Here's how it stands: glsea_curNotice Lake Superior is still almost completely covered in a (thin) layer of ice! MODIS imagery shows this nicely as well: t1.14110.1713.CIS_Great_Lakes.143.250mCheck out how the current ice coverage on the lakes compares to years past at this point in the season: 20140421180000_CVCHDCTGL_0007628828Wow.So there will continue to be a constant risk of air masses getting "refrigerated" by these large bodies of water over the coming weeks.....making them colder than they would be normally.As if this were not enough to be concerned about, next week's weather pattern could be UG-LY across the region...not because of the Great Lakes, but because an upper-level low pressure system seems destined to get "stuck" across the eastern US. This will probably lead to a pattern of cool and wet weather for us. Watch how little this thing is likely to move in a 5 day period:Next Wednesday: wedThursday: thursFriday: friSaturday: satSunday: sunYuck. How cool? How much rain? It's too early to know those answers. But sunny, 70-80 degree days at the end of April and start of May? Forget it.Would be nice to donate some of next week's rain to the West. We are in no danger of a drought here, as shown on the latest Palmer Drought Severity Index: palmerThanks for reading!Eric