BLOG: Detailed Look at the Next Week

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It's a beautiful, warm day today! What about the rest of the week, the weekend and beyond? I thought I would take a few minutes to break down what is heading our way as we get into mid May. While Ohio and western Pennsylvania enjoy a great Thursday, we will be watching the Midwest and Plains states for another round of severe weather this afternoon: day1As the system that will spark the severe weather today tracks east on Friday, the threat for a few thunderstorms will go up in the Mahoning and Shenango Valleys by afternoon. The Storm Prediction Center does not have us in any sort of enhanced risk though...just a "general" thunderstorm zone: day2The NAM model simulated radar at 2:00pm Friday shows spotty shower and thunderstorm activity: 2pmfridayA look at the expected structure of the atmosphere Friday afternoon (via a model "sounding") reveals a fair amount of instability. In the yellow area, air parcels will be "allowed" to continue rising because they will be warmer than their environment. With this much buoyancy in the atmosphere, thunderstorms can get going if there is enough of a "trigger" to force the air to start rising. bufkitprofile (2)Since the "trigger", the cold front, will still be well off to our west Friday afternoon, I expect activity to be very spotty. A lot of us will be able to avoid thunderstorms through the end of the daylight hours.Showers and thunderstorms are most likely with the arrival of that front Friday night and early Saturday. We should see a drying trend during the midday and afternoon Saturday. The chances for precipitation through midday Sunday are illustrated nicely on this graph (from the SREF model):  srefNotice, there is a small chance for a shower or thunderstorm on Mothers' Day. Will not be a washout.Next week will start warm with a couple of chances for showers and thunderstorms. The wettest day is likely to be Wednesday. April ended on a wet note and we have had a few rounds of rain so far this month. 10 day precipitation totals across the region (legend on right): rainlast10Over the next week, we will likely pick up another 1" or so: qpfHave we seen our last 32 degree temperature of the season? Is it safe to plant? Probably, but it's not a 100% certainty yet. This chart shows the minimum temperature over 6 hour increments over the next 10 days, based on the European model. It shows to sub-32 degree readings (32 is red line toward bottom). eurotempsWhat about temperatures in general? While next week starts warm, the end of the week is likely to turn cooler than average. Notice the change in the jet stream configuration from Sunday to next Thursday. Sunday: jetsundayThursday: jetnextthursThe pattern over the US basically reverses, with the big trough of low pressure in the West making its way east during the week.The cooler weather will probably be around for a few days. Temperature anomalies for next 16 days, according to the GFS model: gefsIn the meantime, have a great Thursday...enjoy the warmth!Eric

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