Wednesday, March 27, 2024

Eclipse Day Cloud Outlook - 12 Days Out

You've heard me say this countless times over the years. I really don't put a ton of trust in daily model data further out than 7 days. (Contrary to popular belief, 7 day forecasts are far more accurate than they were 15-20 years ago.)  They do give a nice overall picture of the pattern across a large region like the mid-west or Great Lakes. This provides information like "above normal rainfall or below normal temperatures" which are definitely usable. However, deriving a detailed hourly forecast this far out will always invite problems. Keep this in mind as we close in on Eclipse Day.

For what its worth, here is what the GFS model is showing from late Saturday April 6 through late afternoon Monday April 8th. This is middle altitude cloud cover percentage.

I wouldn't use this information to plan your eclipse viewing as we still have time before the hourly forecast details become better in focus.  If this verifies, cloud cover will be a problem

Another update on Friday.



Eclipse Path


Monday, March 25, 2024

Total Solar Eclipse Part I: What's The Weather Typically Like on April 8th?

NASA

As of this writing it's still a bit too early for a super detailed daily forecast for April 8 in northern Ohio. However it doesn't keep us from looking back at past April 8 weather history.

Here's the weather for April 8 over the last 20 years in northern Ohio:



The NWS office in Wilmington, Ohio has some nice past satellite images showing the wide variety of cloud cover regimes on April 8th.  Here is one comparing 2020 to 2021.


Historically, a cloud free day around the Great Lakes is not very high.

Image courtesy:  Brian Brettschneider, Climatologist

Here is a nice summary of April 8 weather for Cleveland:


Not that I put tons of (little if any actually) weight on deterministic model output but for semi-entertainment use, here is what the American model (GFS) is showing for Monday afternoon, April 8th. What is my confidence of this verifying?  Not high as of this writing. More to come.






Friday, March 22, 2024

Many Tornadoes In Ohio Thus Far. How Does This Compare to Past Years?

 


Uncharacteristically, late February and March thus far, has been a very active period for severe weather across Ohio. While we do see more frequent day-to-day weather fluctuation across the southern Great Lakes and Ohio this month (and April) than in any other month, severe weather doesn't always accompany these changes.

The first severe weather event occurred on February 28th. 

Only 2 hail reports with this first round in late February. No tornadoes.  Most of the storm reports (hail, wind and tornadoes) were across central Ohio.


The second round was far more extensive March. A total of 18 tornado warnings across Ohio and 6 in northeastern Ohio. The NWS in Cleveland also has a great recap here.



5 tornadoes were confirmed in northeastern Ohio. A total of 15 across Ohio.

Storm Reports in March 2024




Radar - March 14, 2024
So far this year's Ohio severe weather reports:



Plymouth, Ohio damage from March 14, 2024 tornado

Is the number of tornado unprecedented for Ohio through late March?  I looked back at the total OHIO tornado count through March since 1950 and separated the totals (red)  with the EF2+ totals (green).  Here is what I found:

Ohio Tornado Count: 1950 - 1985 (thru March)

Ohio Tornado Count: 1986 - 2024 (thru march)

There were brief upticks in tornadoes in the mid 50s and a few instances in the 70s but nothing        really high.  The peaks were 1985, 1986, 2012, 2016 and 2017. Here is the early season 1986 tornado tracks:



Here are some additional bullet points on the graphics above:

*  Two of the three tornadoes in 1992 were EF2+.  One was an EF4.
*  The 1991 tornado was an EF3
*  Six of the nine early season tornadoes in 1986 were EF2+

However, over the last 2 years, early season Ohio tornado counts have rose significantly.  17 in 2023.  26 in 2024 through March. Five of those were EF2 tornadoes. One was in Crawford/Huron counties.

For spatial perspective here is the January through March tornado locations for 2023 and 2024:

Jan, Feb, March Tornado Locations - 2023


Jan, Feb, March tornado locations - 2024

Tornado warnings in 2023 through mid March vs tornado warning in 2024 through mid March:

2023




What were the causes of the uptick last year and this year?  Is this a fluke increase or something that we will see more in the years ahead?

One piece to the puzzle may be the Madden Julian Oscillation (MJO). This was in a high amplitude state in both years.  First image is last Jan through March 2023, second image is this year through late March. (More on this in the weeks ahead)

Strong Phase 7,8 and 1 in March of 2023

Strong phase 4,5 and 6 in March 2024


In my opinion, it's hard to draw a long term conclusion based on only a few severe weather events over a few weeks. So while we had two years with an uptick in early season tornadoes in Ohio, we need to monitor the next 3-5 years to see if a trend develops.




Thursday, February 29, 2024

Tornado Warnings to Snowfall: How Often?


February 28 featured temperatures in the lower and mid 60s with thunderstorms. A handful of thunderstorm warnings with ONE tornado warning in Knox County around 6am February 28.  This tied the earliest tornado warning of the season (2011 was the other year)


Severe weather across multiple states.


Temperatures dropped quickly from mid 60s to the 20s by early evening across northern Ohio. Scattered snow showers develop in the evening with a heavy band of lake effect by February 29 between 5 and 8am.


The drop in temperature impacted the entire Mid-west, Ohio Valley and Great Lakes.  Here is an animation showing the temperatures from 2:45pm Tuesday 2/27 through 2:45am Wednesday 2/29:


Radar loop for the northern Ohio shoreline the following morning (Thursday AM) shows a significant band of lake effect snow:


How often do we go from TORNADO WARNINGS to SNOW in 24 hours? Here is the short list:


How about TORNADO WARNINGS to SNOW in 48+ hours?


So its been 7 years -- March 3, 2017 -- since we had measurable snow 24 hours after a tornado warning!




Friday, February 09, 2024

How Cloudy Was January?


January cloud cover was extremely extensive and long lasting across northern Ohio. Here are the top 10 cloudiest January in Cleveland (based on overcast observations):

When we break down the month into 4 cloud cover categories, this is what we found comparing January 2024 to the last 10 years:  26 of the 31 days had overcast skies. No clear days. 


How did northern Ohio cloud cover compare to the rest of the US in January?
Here is the average amount of cloud cover:  Typically the Pacific Northwest, Great Lakes, mid-west and portions of New England are the cloudiest locations.


Map Courtesy: Brian Brettschneider

Here is the ACTUAL cloud cover rankings for January:

The cloudiest regions were southern Michigan, western New York, southern Florida and yes, northern Ohio.  In fact, southern Florida's cloud cover was top 5 all time. Northern Ohio was 3rd cloudiest.

Map Courtesy: Brian Brettschneider

For comparison, this was the cloud cover ranks nationally for last year (2023)


2002 was one of the least cloudy January months in northern Ohio since the early 1950s.  Here was the cloud cover ranking nationally for comparison.



So why so much cloud cover this January vs other years?

Here is a loop showing where the HIGHS and LOWS are located for each day in January. Blue colors are low pressure, warmer colors are high pressure.  The lower the pressure, the more rising air and typically more cloud cover.
Active Pacific jet stream throughout the month. Early January, jet was across northern Pacific with the southern branch across Mexico and the southern US. By mid month, they partially merged then the southern branch become more dominant. This jet stream configuration kept these frequent low pressure system moving across the central US and Great Lakes. 

Great Lakes ice cover is well below average. This has kept the relatively mild water exposed to the frequent weather systems during the month. While the Great Lakes are not solely responsible for the cloud cover, they have contributed to it.








Monday, January 22, 2024

Snow Totals From Last Week's Storm?

Snow started early Friday morning and ended late Saturday evening/night.


Here are the individual totals for each region of northern Ohio:








Seasonal Snow Totals Through January 22 - Last 10 Winters:


Comparison between last winter and this winter through January 22 across northern Ohio.