History of 90 Degrees Days In Cleveland

How many 90 degree days have we had in Cleveland since 1980?

What is the 90 degree temperature trend per decade over the last century in Cleveland?

What month are we more likely to see the most 90 degree days?

A Look at June...The Outlook for July

Will July be cooler or warmer than average?  That's the $64,000 question.

Summer or winter outlooks are the most sought after of forecasts--the 8day forecast is a close second.  Face it.  People love to look into the future.  What is the first think we think of when planning an outdoor wedding reception or graduation party? The weather.  We search and search for that elusive piece of weather information that might tip the scale in favor of ordering a tent.

In the weeks and months leading up to the party, we become manic.  The seeking of that long range outlook  is tantamount to investigating what's in Area 51. We are attracted to it because we see it as a diamond in the rough.  Yet in reality, any long range outlook, much like Area 51 on a map is a gray area filled with fuzziness. 

When people call or email questions about the weather for specific days 3 or 4 weeks out, they don't care that its beyond our ability to give them specifics.  They just want weather information to hold onto even if it might be that "gray area filled with fuzziness". 

One thing to always keep in mind about "Long Range Outlooks" is that they are TOTALLY different than daily forecasts both in how they are created and the parameters used in their creation.  We can't look at the weather in Chicago yesterday and develop a long range outlook for the month ahead.  But we can study an evolving La Nina or El Nino, for example, to find linkages to overall shifts in our weather pattern that ultimately affect our weather in Northern Ohio.  For example:  Does a developing La Nina in the Pacific lead to a pattern conducive to cooler temperatures? Or does an El Nino lead to more rainfall in Ohio? We are not after specific weather conditions for specific days but a general outlook for weeks and months in the future based upon generalized patterns.  If you are looking for the high temperature 24 days from now, the Long Range Outlook isn't designed for that.

June is half over.  Conditions have rapidly dried out; temperatures through June 15th have been near normal.  Based on what we see now, what general pattern might we see in July?

Look at the disjointed nature of the upper level winds. Each one of these "buckles" in the flow allow a trough or front to move through bringing small chances of rain followed by a temporary cool down. Notice no ridge of heat...yet. 

The HEAT RIDGE across the eastern US from last year and 2010 hasn't developed.   The Sonoran ridge (SW ridge) has been weak. The Bermuda High is still out in the Atlantic.  What lies in the middle are temporary shots of cooler air. 

This dry and warm stretch through Fathers' Day weekend has been the exception.  Here, the ridge out west shifts east boosting temperatures. The red dot is OHIO.

Beyond 7 days, we need a different set of tools to determine the pattern.  Normally, computer projections lose their skill further out in time. In an effort to diminish this effect, we can run the computer projection multiple times with different initial conditions. After, say 20 runs, an ensemble forecast is created by taking the average of all 20 runs.  This ensemble smooths out the chaotic atmospheric elements making a long range projections more accurate.  Its not perfect but its a Godsend when making long range outlooks.

I've hinted at a "cool down" the last 7+ days of June.  Why?  Look at the ensemble for June 28th.  Heat shifts back west. The Bermuda high stays out at sea.  In between lies cooler and hopefully unsettled weather (we need rain!)

La Nina is gone. El Nino is showing signs of returning in the fall.  Since no large scale drivers are in place like last summer or 2010, we utilize other smaller scale, faster moving signals that originate in the Indian Ocean and move into the central Pacific Ocean.  These faster moving disturbances can create a short-lived La Nina or El Nino signal which can dramatically alter the pattern across the US.  Many long range forecasters linked these disturbances  to the heat we had in late May.  It seems that this "Indian Ocean disturbance" MJO will once again be the driver of our pattern into early July.

Based on the July years that best match the conditions this year, we came up with this:

So expect another long stretch or two with 5-7 days of heat in July with another "cooler" reprieve.  Heat will come and go.  Overall, July seems to average near normal over the 30 day period.



Let's see if this outlook hold true...

The Basics of the Early Universe

I have been working on a study of some Cleveland climate data recently. Compiling the data was very time consuming.  Patience...patience.  The results will come later on this week.

In the meantime, take a listen to this presentation about the universe from Sean Carroll, theoretical physicist at Caltech. He describes the early universe in very easy-to-understand terms. The study of the early universe and the reason why EVERYTHING around us behaves the way it does has always captured my attention. It makes me think in many dimensions outside the box.

Fortunately, youtube offers a ton of information tightly compacted in video form that only takes 10 or 15 minutes to watch.

Transit of Venus TUESDAY EVENING

Venus will pass in between the sun and the earth producing a silhoutette--the dark spot shown in this video below (from 2004).  Unlike space station passes, this one will take several hours to completely pass through our view.

Why is the transit of Venus so special? 

First, planetary transits like this don't happen very often. The last transit of Venus was in 2004.  The one previous was in the 1800s.  The next one won't occur until 2117 and then again in 2125.

Second, transits like Venus allow scientists to study the sun in greater detail.  In the 1800s and early 1900s, the transits were sought after events. One explorer made the trip to Tahiti to best view a transit of Venus in the 1700s. The transit viewings back then probably didn't help in measuring planetary distance as much as they thought.  Primatative equipment and other atmospheric phenomena not known cast an even harder shadow on their results.

Still, you can imagine what it was like to see this hundreds of years ago when falling off the edge of the earth was considered modern scientific truth!

Edgewater Park in Cleveland is the place to be to properly view the transit of Venus. Never look directly as the sun! Download this map from NASA for more details http://eclipse.gsfc.nasa.gov/OH/tran/TOV2012-Fig02.pdf

The transit starts at 6:04PM and finished when the sun disappears below the horizon at roughly 8:55PM

Partial Solar Eclipse Sunday at 8:22PM

A great video and disgram on what a Solar Eclipse is and how to best view it without damaging your eyes.

Viewer Phonecall and My Hypothetical Response

Invariably after a "big' weather event, angry viewer phone calls follow.  Usually, it’s the same people. The reoccurring characteristic of these callers is that they never Identify themselves.  They just start venting once they hear the voice mail beep and abruptly end the call often times in mid-sentence.  

A few things before you begin:  This post chronicles a really bad phone call. We don't get them that often. 99.9% of viewers are great and are a joy to talk to both on the phone and in public.  It's that 0.1% who frankly, drive you nuts.  I want to reiterate that the first part of the call is the actual "transcript". The latter 2/3 is pieced together with my fantasy responses.  I purposefully used "enter city" in the place of a specific city.   Here we go with the call.

Viewer:  "What happened to all this rain?"

Me: "Whom am I speaking with?"

Viewer:  "You said it was going to rain all day?"

Me: "I am sorry sir. What is your name? Where are you calling from?"'

Viewer:  "You said it was going to rain all day?"

Me: "Your name, sir...where are you calling from?"'

Viewer: "Dave from  (enter city)."

Me: "Dave, I believe I said that the rain would be scattered and not everyone would see rain. I most certainly didn't say it would 'rain all day.'"

Viewer: "I got no rain in (enter city).  My wife and I think you need to go back to weather school."

Normally, the conversation would end here with me saying something innocuous like "I'll take that under advisement" or some other canned, hyper-neutral response like "thank you for your feedback." If the conversation were to take a turn to the dark side, this is where it happens.  So to the dark side we go.  The viewer portion below is real.  My response below is a purely hypothetical retort that often goes through my head in the heat of the moment.  I remind myself that it takes a level of discipline and nicety that rivals Sister Teresa not to snap back with a more piercing, direct response when taking to a belligerent viewer.   Thank goodness for that mental filter that prevents thoughts from becoming words.    

Remember, my responses are more therapeutic than literal, a cathartic moment for me as the rain continues to fall today so PLEASE don't take it seriously. I’m just having a little bit of fun. Let’s continue with the rest of the phone call...

Me: "Sir, the very nature of atmospheric behavior has a built in element of randomness.  While we have equations and computer projections that do a very good job of estimating the position and strength of rain/storms a certain time intervals into the future, there and always will be limitations...

Viewer: "...You can take your computers and fancy math stuff and all of your Facebook pictures and throw them out the window...I can do a better job by looking out my kitchen window"

Me: "Sir, we all believe that our weather outside our window is a microcosm of the overall weather picture.  Most times, this isn’t the case unless we are experiencing a widespread area of tropical spring rain which happens maybe 3 or 4 times a year"   

Viewer: "Why don't you get it?  You're fancy technology sucks and doesn't do ANYTHING! Forecasts were better 20 years ago than now..."

Me:  "Trust me, sir.  I understand what you are saying but your wrong.  Forecasting is MORE ACCURATE in recent years.  This has been..."

Viewer:  "...Do you even know where (enter city) is?"

Me:  "Sir, I've spend many a day in (enter city) as a kid visiting my cousin.  I can't tell you how many 4th of July's I've celebrated in (enter city) and other surrounding communities.  

Viewer:  "You never mention  (enter city) at all in your weather."

Me: " I absolutely do!  I just can't mention  (enter city) in every weathercast.  Its next to impossible to mention the 1000+ different communities in northeastern Ohio in a little under two and a half minutes."

Viewer:  "Why don't you like  (enter city)?"

Me: "Sir, I just said I try to mention  (enter city) as much as possible.  The universe doesn't revolve around your (enter city) There are other locations we need to worry about just as much"

Viewer: "Go back to weather school where you can learn how to be accurate."

(At this point, the conversation is now spinning back in on itself; a runaway collapse with no way of resuscitating it. At this stage, the hopes of a rational discussion are almost zero. My attempts are futile)

Me: "Sir, my point is that while spotty showers didn't occur in (enter city) where you live they did occur in many other places. So, my forecast of 30% coverage was accurate.  Each of us has an atmospheric horizon--dome of weather influence which surrounds us at any given point--and its very small.  Weather still occurs outside of what we can see."

Viewer:  "You are full of yourself.  Your no damn psychologist. You are a (expletive) horrible weatherman..."

Me: "Sir, this conversation is going nowhere.  If you want to have a rational and objective conversation about all of the variables that go into the mechanics of meteorology and how our cognitive biases shape our perceptions on the accuracy of weather forecasts, I am all in. If you want to continue to use inappropriate language and behave in a disrespectful manner, this conversation is over.

Viewer:  Dead silence...(Click)

I can only imagine what customer service associates go through each day.

Today's Complicated Storm Setup

This spring has been void of severe weather and widespread heavy rainfall here in Northeastern Ohio.  The setup today through this evening is different from the last several cold frontal systems in that most of the parameters needed for heavy rainfall and severe weather will be present:

Courtesy: American Wx

*  Humidity is climbing; precipitable water (atmospheric moisture) levels will climb sharply
*  Convergence (different air masses slamming together) along the warm then cold front at just the right time (late afternoon/early evening) when the temperatures are the warmest
*  Atmospheric energy will be high



What makes today's weather difficult is that we have two completely different sets of conditions present embedded within this system. Warm front is catching up with the rain that outran it late last night.  Warm frontal characteristics usually promote "clusters" of storms versus well-defined storm "lines". This morning, the cluster is well ahead of the high dew points. This is evident by the area of rain/storms in northwestern Ohio stretching out over Lake Erie.  The cold front trailing behind is driven forward by colder air lurking behind.  These storms--unlike the cluster earlier--will move into Ohio mid to late afternoon fueled by high dew points and sparked by the energy with the cold front.

CLICK HERE FOR THE UPDATED OHIO RADAR

The problem today?  The cold front is catching up to the warm front. The energy from the cluster of rain/storms over Lake Erie is blending together with the energy to the south resulting in a blending of the two areas of rain and storms. The physics of one doesn't necessarily describe the other all of the time! This makes the forecast details today very difficult to nail down. 

The Storm Prediction Center has us in a "slight risk"

Radar is showing one cluster in western Ohio ahead of the warm front.  Its not moving very fast as of 10AM.  If anything, its outrunning the warm front.  As the warm front lifts north, it will supply more energy (mid level lift) to enhance the cluster further.

The second wave is now developing along the cold front.  Given breaks of sunshine in southern Ohio and the increase in humidity along the cold front, the late afternoon/early line of storms will reach severe limits with locally heavy rainfall especially across our southern counties.

Now its just adjusting the timing of each "spoke" of rain and storms that jut out from the main area. More updates later today

How Can the Past Winter Pattern Influence Hurricane Season?

Earlier in the year, I explained the drivers of this winter's record setting warmth and lack of snow. At the top of the list are the strongly "positive" behavior of the North Atlantic and Arctic Oscillations. (Read my earlier post which explains the specifics of each oscillation) The effects that each oscillation produces can linger for months even after the numbers positive or negative have stabilized. In most seasons when one or more teleconnection is abnormally strong (as was the case the last 3 winters), the change in air pressure, temperature and ocean temperature, the dynamical imprint on the atmosphere can be much greater.  These imprints seem to trickle down into the large scale wave changes and stochastic processes that drive our weather patterns.

A great example of these changes are seen in the Atlantic Ocean sea surface temperatures. Remember the last few winters consistently cold and snowy pattern?  This was largely driven by record low Arctic and North Atlantic Oscillation levels.  Remember that the North Atlantic Oscillation are caused by changes in pressure of the Icelandic Low and the Azores High. If the Azores High becomes weaker, the Icelandic Low stays north/stronger, the NAO is negative, more frequent cold air outbreaks/more clipper snows.  When the Azores high becomes stronger, the NAO goes positive, not as much cold air.  

What does this have to do with hurricane season?  Look at the pressure patterns over the Atlantic in the spring following a strongly NEGATIVE NAO winter. The Azores High (shown in light green) is smaller and weaker.

Dec, Jan and Feb 2009-2010

Dec, Jan and Feb 2010-2011

The steering currents around the high stay weak.  These weak trade winds from the east don't cause upwelling of deeper colder water. Here are the steering winds over the last 2 winters into early spring.

  

Now this early spring

The turnover of water is much smaller which allows the sea surface temperature to increase.  Here are the Atlantic sea surface temperatures in early spring in 2010 and 2011 after a STRONGLY NEGATIVE NAO winter.  Very warm water is located in the tropical storm development areas.

Now look at this winter's NAO signature.  Remember our mild pattern?  Look at the Icelandic Low and the Azores High.  The High is very strong which kept cold air locked up in Canada.   

The Icelandic Low stays further north which kept the flow across the US and the Great Lakes out of the west NOT THE NORTHWEST.  The Azores High allowed the steering currents to stay strong which is now causing the upwelling of water off of Africa and into the central Atlantic development region.

Currently, the Atlantic Sea Surfaces are much cooler than in springs past covering a larger area.  

So the positive NAO this past winter was a result of a stronger High in the central Atlantic. This strengthened the trade winds which caused upwelling of cooler water which has led to a cooler Atlantic development area.

Will this result in fewer tropical storms developing earlier in the season?  Will this result in less tropical storm or hurricanes affecting the east coast or Gulf coast?  We shall see...

Late Season April Snow On The Way!

Late April snowfalls are indeed rare birds.  The last time Northeastern Ohio had measurable snowfall after April 20th was in 2005 when more than a foot of wet snow fell between the 23rd and the 25th. Normally, it takes me 35-40 minutes to drive home. That evening after the 10PM news, I didn't get home until 1:45AM!  25 mph along the interstate straddling tracks in the snow made by the semis ahead of me. By far the worst drive through snow I've ever had.

CLICK ON IMAGE FOR CURRENT OHIO RADAR

The biggest concern will be for downed powerlines across central PA. Leaves on the trees in early spring have the ability to hold more than leaves in late fall. Copious amounts of heavy wet snow will no doubt bring power lines down.  Luckily in northern Ohio, the amounts of snow will be far less.  We have several factors working against widespread snowfall:  1) The track of the storm steers the moisture north, away from northern Ohio.  2)  The ground temperatures are in the lower 40s.  3) The Lake Erie water temp is 50.  Still, evaporative cooling (cooling process within the cloud as precipitation falls--the chill you feel when you step out of the shower) will cause temps to drop sufficiently enough during the night low enough to allow snow to accumulate in spots.  Here are projections through midday Tuesday.

Here are the times in Cleveland when we had snowfall after April 20th since 1948:

2005     April 23-25th  12.4"

1971     April 24            0.1"

1968     April 25            0.2"

1967     Apri 24             0.1"

1963     April 30            0.3"

1953     April 20-21st    1.7"

Do We Need More Spring Rain?

The quick answer is a surprising YES!

The frequent rains of February proved to be a little misleading. Thoughts of another record setting spring like last April through June have proved to be premature.  The hottest March on record with several days of 80+ rapidly dried the ground out across northern Ohio. Soil conditions were still too wet for farmers to turn over the fields. April has proved that weather patterns can change drastically.  Only 0.33" of rain at Hopkins Airport with average temperatures running a degree above normal. (Expect the cool weekend to lower the monthly average). As of April 18th, as I drive into rural Lorain and Medina counties, many farmers' fields seem ready to go.

Look at last year's April rainfall compared to average.  Most areas from upstate New York through Ohio to northern Mississippi were more than 10" above normal. The trend continued through June.

Now this April. Quite the opposite but not to extreme. Rainfall is slightly below normal going back 60 days.

Soil moisture over the last 3 weeks has dropped significantly in the east.

Our pattern that shows a somewhat persistent zonal to WNW flow aloft still concerns me. The last two weeks of April should feature near normal temperatures with a few shots of cooler air. If the cooler air is accompanied with clear skies, expect a few more frost advisories to be issued so keep an eye on the nighttime forecasts. The WNW/NW flow could bring weak fronts with less frequent hard rains.

Should you plant your garden in early May? I wouldn't.  No way.  I was burned one year as a late May freeze wiped everything out.


How will the rest of the spring shape up?  Here are the questions to ask:


* No more La Nina. Does the neutral ENSO conditions prevail?
* Where will the warm/cool pools develop in the Atlantic
* Will the PDO continue to weaken?
* Will the northern Pacific warm pool back to the west and cool?
* How much variability will the MJO introduce into the pattern?
* Will any widespread precipitation extremes in the middle of the continent (wet or dry) enhance/weaken storm systems before they can impact Ohio?