Tag: Meteorology

Kenny Asks, Who Should We Trust?

This email just came in:

Hey Geoff,

Good Luck in your move. So I have to ask…Who should we trust for weather now ?

Kenny

Good question. I’ve gotten it a lot.

First, there is little difference in accuracy between the four Connecticut TV stations providing a forecast. Nearly everyone’s correct nearly every day!

Don’t stop reading here. There are differences other than the numbers.

I do have a problem with the automated numbers you see on many websites. By and large they are correct, but they’re usually not double checked by humans. I’ve seen stupid forecasts posted that humans would never allow.

To a viewer there is no difference between 66&#176 and 68&#176. A snow forecast of 5″ demands the same action as one of 8″. These differences are not very important. Don’t dwell on them.

The difference in weather forecasts is how the forecaster tells the story. Is his/her presentation understandable? Does he/she leave you with actionable information?

Watch the meteorologist you best understand, because accuracy doesn’t matter if you can’t translate their words into usable info.

I know most of the meteorologists in Connecticut. They are all honorable. None of them benefits from hyping the forecast–and they don’t.

Find someone you trust. In that regard meteorology is like everything else in life.

The About To Lose Her Mind Skew-T Tweet

I had her send me the PDF then got her Skype address so we could share the screen. It didn’t work and Skype crashed my router!

Screen sharing, allowing you to see what’s on my screen, was a great free feature on Skype. It looks to be a pay feature now! Anyone know where this can be accomplished without charge for the next time?

I got a desperate plea on Twitter tonight. It was from a Facebook friend whose name I recognize scrolling down my wall in the middle of the night.

@geofffox if you get this tweet in the next 20-30 mins, please tweet me back. About to lose my mind on a Skew T assignment.

I saw it 29 minutes later and answered.

Skew-t plots are vertical depictions of the atmosphere. Weather balloons are launched twice a day around-the-world. A skew-t plot is a good way to display its data.

I don’t use them often. They’re somewhat old school. There are other tools available now which eliminate the middle man.

I had her send me the PDF then got her Skype address so we could share the screen. The screen share didn’t work and Skype crashed my router! Thanks.

Screen sharing, allowing you to see what’s on my screen, was a great free feature on Skype. It seems to be a pay feature now! Anyone know where this can be accomplished without charge for the next time?

We kept our screens filled with the skew-t and talked as if we were on a speakerphone. It didn’t take more than a few minutes for a lightbulb to go on over her head! It was 20 minutes before the quiz had to be submitted for online credit.

Oh my goodness. You have no idea. I’m afraid to even know what grade I might have gotten on that if not for your help.

This is my good deed for the year. Please, no one else ask.

How The Season’s Change Affects The Forecast

Because of its tilted axis the Earth is heated unevenly. Its surface is also rough and irregular. All of this creates temperature and pressure differences which cause winds–especially upper air winds.

My guess is you don’t pay attention to the weather as much as I do. We’re about to enter a transition period. Meteorology works a little differently during the warm months.

Because of its tilted axis the Earth is heated unevenly. Its surface is also rough and irregular. All of this creates temperature and pressure differences which cause winds–especially upper air winds. Temperature contrasts are stronger in the cold months and that drives everything!

When the upper winds blow strong weather systems move quickly. That’s what we’re leaving.

From now until the fall weather systems will move slower. Fronts and air masses will be a little more spongily defined.

There are certainly forecasting differences. Timing becomes tougher. On convective days very small, but nearby areas will sometimes have radically different weather.

Of course you’re less critical because the forecast usually has less impact this time of year. I appreciate that.

A Year Of Exceptional Weather

You’ll excuse me, but back in January I was a little numb! That being said it’s really amazing just looking at the stats! Three major snowstorms and two smaller ones all in fourteen days!

Amy, the assistant news director, came to me a few days ago. We’ll be doing recaps of the top stories of 2011. Four of the top ten are weather related. She asked if I’d package them.

She’s my boss. I can’t say no. Actually, I don’t want to.

These year-end packages are a staple of news in an otherwise slow time of year. There’s enough time available to show detail.

This is as close as I get to documentary work. We all lived through a year of exceptional weather!

I wrote about the snows of January tonight. It airs next Monday.

You’ll excuse me, but back in January I was a little numb! That being said it’s really amazing just looking at the stats! Three major snowstorms and two smaller ones all in fourteen days!

Unrelenting. Records set left and right.

Roof rakes!

Brian, an editor at the Courant, showed me their searchable database with full text from the paper. Incredibly valuable.

Still to come the Springfield tornado, Irene and the October snow from hell!

It’s funny how things change. At my last job I was discouraged from doing this kind of thing. I still can’t figure out why.

The Tragedy At The Indiana State Fair

It’s easy to look at the radar and think everything is obvious. It is not. That was proven this weekend in a tragic loss of life.

Like you I have been dumbfounded after seeing the video from the stage collapse this weekend at the Indiana State Fair. There is a blog with really excellent analysis of what happened, including a play-by-play of the radar imagery available.

If you’ve been watching Rachel and me on FoxCT you probably remember a storm last month where we pointed out exactly the same feature that caused the trouble in Indiana: a gust front.

These are easily visible on radar, but only if you know what you’re looking for!

After reading these storms were being monitored by a public safety officer on his smartphone Rob White, the blogger who did the analysis, added:

On his smartphone? Really, the Special Operations Commander and fair Executive Director were monitoring the potential for incoming severe weather on a smartphone? I’m sure many of the fans out in the crowd were as well, but most of them weren’t expecting to make a life or death decision on it.

This comes back to a point that I’ve tried to make many times on this blog. When it comes to severe weather safety and preparedness at a major public event, the organizers and/or managers of such an event need to leave it to a professional to monitor the weather for them – not a layman watching the weather on a smartphone (or even on a computer via the internet for that matter).

I couldn’t agree more. It’s easy to look at the radar and think everything is obvious. It is not. That was proven this weekend in a tragic loss of life.

This is the video of a tragic event. Lives were lost onscreen. You should consider this before clicking play.

I Keep Track Of The Weather

“Southeastward moving.” That’s the scare line for me. Our strongest storms move northwest to southeast.

I don’t know how other people do their jobs, but I keep track of the weather while I’m off-the-clock. The atmosphere has a rhythm. You want to stay in the rhythm. I look at maps, usually briefly, all the time.

The Storm Prediction Center just issued Moday’s national outlook. We’re squarely inside the “slight risk” area for severe storms.

Slight doesn’t sound bad, but it’s better than 50/50 if you’re in the slight risk area you will get a severe weather box later in the day! I’ve been doing this a long time. There is a rhythm.

I’m going to post SPC’s technical discussion, but feel free to skip this section. It’s full of jargon and technical terms plus nearly all the Weather Service bulletins are all caps. Sorry.

…NORTHEAST STATES/NEW ENGLAND…
EASTERN CANADIAN UPPER TROUGH WILL DIG SOUTHEASTWARD OVER QUEBEC/EASTERN ONTARIO TOWARD NEW ENGLAND/NORTHEAST STATES THROUGH TONIGHT…WITH ASSOCIATED COOLING/STRENGTHENING CYCLONIC FLOW ALOFT AS FAR SOUTH AS THE MID-ATLANTIC STATES. WITH RELATIVELY STEEP LAPSE RATES/SUFFICIENT CAPE BY AFTERNOON…MULTIPLE SOUTHEASTWARD-MOVING BANDS OF STRONG/SEVERE TSTMS SHOULD DEVELOP/INCREASE THIS AFTERNOON…WITH SUCH DEVELOPMENT FOCUSED IN VICINITY OF A SURFACE TROUGH ACROSS NEW ENGLAND/NEAR THE EASTERN SEABOARD AND/OR ALONG ONE OR MORE SOUTHEASTWARD MOVING WEAK COLD FRONTS ACROSS THE NORTHEAST/NEW ENGLAND. SUSTAINED MULTICELLS ALONG WITH A FEW SUPERCELLS CAN BE EXPECTED…WITH DAMAGING WINDS/SEVERE HAIL AS THE PRIMARY HAZARDS.

“Southeastward moving.” That’s the scare line for me. Our strongest storms move northwest to southeast. In the Plains the strongest storms head to the northeast.

SPC also says the biggest risks are strong winds and large hail. Tornadoes seem unlikely, though you can have comparable damage from microbursts.

The Rapid Refresh model which did well on timing this past Friday shows the system entering Connecticut early afternoon. It will build as it heads in our direction. The computer readout resembles a snowball which grows as it rolls downhill.

This isn’t the last time I’ll look at maps before going to work today.

Another Tornado Outbreak

I am as perplexed by this vicious season as much as anyone. I understand the atmospheric set-up. That part’s no surprise.

You will be excused if you don’t hit the Storm Prediction Center website especially on this idyllic day in Connecticut. They are expecting more doom and destruction in the Midwest. It’s scary. It’s sad.

Here’s how they set the plate. The following outlook was issued long before any watches or warnings. Consider it a general heads up!

PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1226 PM CDT WED MAY 25 2011

…MAJOR TORNADO AND SEVERE WEATHER OUTBREAK EXPECTED OVER PARTS OF
THE LOWER MISSISSIPPI…MID MISSISSIPPI…AND LOWER OHIO VALLEYS
THIS AFTERNOON AND TONIGHT…

THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE
DEVELOPMENT OF NUMEROUS TORNADOES…WIDESPREAD DAMAGING WINDS…AND
LARGE HAIL OVER PARTS OF THE LOWER MISSISSIPPI…MID
MISSISSIPPI…AND LOWER OHIO VALLEYS THIS AFTERNOON AND TONIGHT.

THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE

CENTRAL AND EASTERN ARKANSAS
CENTRAL AND SOUTHERN ILLINOIS
CENTRAL AND SOUTHERN INDIANA
WESTERN KENTUCKY
CENTRAL AND EASTERN MISSOURI
NORTHERN MISSISSIPPI
WESTERN TENNESSEE

The map I’ve attached show how tornado watches stand as I type this. Obviously those will pop on-and-off through the night.

I am as perplexed by this vicious season as much as anyone. I understand the atmospheric set-up. That part’s no surprise.

The question is why are all the factors gelling so often this year?

Bad luck? Probably.

At this point I’m dismissing any tie-in between this severe weather and global warming. You can’t easily connect anecdotal events with climate.

I am closely watching our chances for severe weather Friday and Monday.

Today’s Thunderstorms – New Tools

These thunderstorms forming overhead gave me a chance to look at a new tool: The High Resolution Rapid Refresh model (HRRR). It’s your tax dollars at work.

We heard the first boom around 20 minutes ago.

“Hear the thunder?” Helaine asked. It was tough to avoid.

Over on Facebook Diane Campbell posted, “Just heard the loudest rumble of thunder I ever heard in my life! =(( scared me!”

It was in the forecast – phew! Bad weather isn’t so bad if it’s expected. That’s my very limited perspective.

These thunderstorms forming overhead gave me a chance to look at a new tool: The High Resolution Rapid Refresh model (HRRR). It’s your tax dollars at work.

The HRRR is the only hourly updated, radar-initialized, storm-resolving model running at this time over the US (or internationally), to our best knowledge. As a higher-resolution nest inside the hourly-updated Rapid Refresh the HRRR is designed to provide rapidly updated model guidance on convective storms for

  • air traffic management
  • severe weather forecasting
  • NOAA National Weather Service Warn-On Forecast
  • eventually provide improved background fields for NWS Real-Time Mesoscale Analysis
  • provide improved basis for other aviation hazard forecasts (e.g., wake vortex, ceiling, visibility, turbulence, inflight icing, terminal forecasts)

Allow me to cut through the mumbo jumbo. HRRR is very high resolution in both time (15 minute increment output) and space (3km resolution). It is a short range model that only goes out 15 hours from initialization. Since it takes a while to process you’re left with 12 or 13 usable hours.

Typically models give hints not full solutions. You can never take the exact placement of features as a given. I expect the HRRR will change that!

I am looking at the 1730z radar image and predicted radar image. They’re pretty close&#185. Not 100%, but much better than what I’m used to seeing.

If HRRR is as good as I hope these showers and thunderstorms will be gone by 5:30 pm (give or take a little).

Progress is good.

&#185 – Unfortunately, the maps are different domains and projections. That makes overlaying them impossible.

The Weather’s Not Weird–Honest

This isn’t going to be what you expect.

I hate to quote the Wall Street Journal. It’s moved a little right of center in recent years. This is a story about climate change which has became as politically charged as it is scientifically controversial. A left or right spin could make a difference in how things are presented.

That being said the Journal has an eye opening revelation from one of its European editorial writers.

If you’ve gone through the past few years thinking weather’s become weird be prepared for your eyes to be opened… or maybe closed. This isn’t going to be what you expect.

Weather hasn’t really changed! As its source the Journal uses the Twentieth Century Reanalysis Project from NOAA which “contains objectively-analyzed 4-dimensional weather maps and their uncertainty for most of the 1900’s.” “Objectively-analyzed” means unbiased. In other words we now have trustworthy detailed weather maps for the pre-satellite early 20th Century!

As it happens, the project’s initial findings, published last month, show no evidence of an intensifying weather trend

Basically unusual weather has always been with us. I think we’re more conscious today because it’s easy to see what’s going on everywhere. Bad weather which might have evaded you, like an Australian typhoon, is now front-and-center on your TV and/or computer.

Back to the Journal article.

“In the climate models, the extremes get more extreme as we move into a doubled CO2 world in 100 years,” atmospheric scientist Gilbert Compo, one of the researchers on the project, tells me from his office at the University of Colorado, Boulder. “So we were surprised that none of the three major indices of climate variability that we used show a trend of increased circulation going back to 1871.”

I guess I’m a little surprised too.

Anyone Sick Of Winter Yet?

When snow approaches people want to know as much as we know even when we don’t know all that much!

Over on Twitter the ‘house account’ for the Meriden Record-Journal newspaper just tweeted, “Reports of snow possible towards the end of the week/weekend. Anyone sick of winter yet? #ctweather”

It didn’t take long to see a reply, “I am sick of winter and you can quote me!” That was from me.

Not even two weeks into winter officially and it’s already like being on a bad blind date looking for a strategy to bail. I need a winter wingman!

We’ve only had one real snowstorm so far, but this has been the windiest winter in a long time. December was a decidedly cold month–colder than even December should be. Now there’s the chance for snow as we head into the weekend.

Here’s one thing last winter taught me: Don’t commit too far out!

It’s OK to say what looks likely, but foolhardy to make that anything more than an advisory for planning early on. If you say something will happen with certainty you will certainly be burned! I still have scars.

120 hours out an error of a mile an hour (or less) can be the difference between heavy snow and no snow! I’m not that good. No one is.

I got a note from Dr. Mel this morning. We often chat when these larger systems approach. It’s good on both sides because speaking your mind and defending your ideas is as helpful as listening!

WE HAVE NOT ONE BUT THREE DIFFEENT CIRCULATIONS TO WATCH FOR THE END OF THE WEEK…

BUT IT IS ANYONES GUESS FROM THURSDAY NIGHT ON. THE KEY WILL BE THE TROUGH LINE. AS LONG AS IT IS SOUTH OF THE AREA, A CHANNEL FOR ATLANTIC MOISTURE WILL EXIST AND WE COULD GET BANDS OF MOD.SNOW IN THOSE SPOKES.

AS USUAL ALL THE MODELS FLIP FLOP…THE 12 Z KEEPS THING POORLY ORGANIZED, AND SHIFT THE TROUGH LINE NORTHWARD…MUCH DIFFERENT FROM OO AND 06Z RUNS.

WE WILL JUST HAVE TO WAIT WATCH…I HEAR THAT A LOT LATELY

People have accused me (and I suppose all forecasters) of hyping these storms. Why? You are just as likely to watch if we claim honest uncertainty as divine insight!

When snow approaches viewers want to know as much as we know even when we don’t know all that much!

The Not Really A Blizzard Blizzard

Basically there was so much wind the snow was blown into drifts which had the effect of compacting the snow.

I am bushed! I know my job isn’t physical labor, but today it was very draining. I started around 1:00 PM and went until 11:35 PM.

A lot of people do a whole lot more. How do you do that?

From a meteorologist’s standpoint today was very interesting. I know now there’s no way I could have predicted snow accumulations accurately. I think most people caught on to that viscerally. Basically there was so much wind the snow was blown into drifts which had the effect of compacting the total.

This is one of those cases where one plus one doesn’t equal two! It was possible to have an inch of snow one hour, an additional inch the next and end up with under an inch of snow!

How many feathers does it take to fill a bag? Similar quandary.

The wind was… still is at this hour… crazy. We seldom get 50 or 60 mph winds, but we did tonight and they were widespread.

I spent the my time on the air telling people to stay off the roads, but by the time I left the building the snow had temporarily let up and I made a dash for the house in Helaine’s 4WD SUV.

I took city streets instead of my usual missile flight up I-91. The main streets were plowed but very slippery. Once I turned onto the squiggly road that climbs my hill things became a little more dicey. The last half mile to my house had no visible tire tracks!

By the way, I stopped the car to take these photos. With all of you at home stopping in-the-middle of the road was no problem. Thanks.

Actually, I take that back. At one stop I had a little difficulty regaining my traction. A quick shift to reverse and a few feet of rollback solved the problem.

We had blizzard warnings tonight and certifiably rotten conditions. What we didn’t have (as I warned in a post a few days ago) was a blizzard! The official parameters are so stringent I’m not sure we ever could!

Maybe blizzard needs to be redefined.

The Buffalo Snowmap

Here’s a map from the Weather Service recounting this storm. The 1-3 foot area is only 12 miles wide! It’s not much more than 6-7 miles from three feet of snow to zero.

Earlier today I posted my Lake Effect snow story. If you read it one of the points I tried to bring home was how narrow these bands really are. Now documentary proof!

Here’s a map from the Weather Service recounting this storm. The 1-3 foot area is only 12 miles wide! It’s not much more than 6-7 miles from three feet of snow to zero.

Click the map to see a larger view.

My Lake Effect Snow Story

The best way to explain Buffalo’s lake effect snow is with a little story. It was the day Helaine and I got our marriage license. Because we were getting married in Pennsylvania we had to drive to Erie, PA.

This evening at 4:45 the Weather Service office in Buffalo relayed a report from West Seneca, NY. A volunteer observer measured 32″ of snow from Thursday’s persistent lake effect snowband.

I wasn’t surprised.

Winter weather in the Buffalo area is brutal. The city itself gets ‘only’ around 80″ of snow per year. The snow belt south of town can get as much as 150″. East of Lake Ontario, closer to Syracuse, it’s even worse.

The area east of Lake Ontario is the “snow capital” of the east. The higher elevations between Watertown and Syracuse, commonly known as the Tug Hill Plateau, receives of more than 200 inches a year. In fact, the town of Hooker, located in Lewis county, recorded 466 inches of snow during the winter of 1976-77! – source: National Weather Service Buffalo Forecast Office

I lived in Buffalo from 1980 through 1984. I will never forget those winters. It seemed to snow nearly every day even if only flurries.

The best way to explain Buffalo’s Lake Effect snow is with a little story. It was the day Helaine and I got our marriage license. We were living in Buffalo. We were getting married in Pennsylvania. The closest place to get a license was Erie, PA, about 100 miles away.

As we left our apartment skies were cloudy. By South Buffalo there were flurries. We paid our toll and got on the New York State Thruway. We passed West Seneca in heavy snow.

I was used to Western New York driving conditions so we continued southwest on the Thruway paralleling Lake Erie’s shoreline. By Dunkirk the snow was back down to flurries. Soon we were in bright sunshine. I remember the skies over Erie being blue and cloud free!

We paid our money, showed our blood tests (another story for another day–blood tests almost kept us from getting married) and got our license.

As we headed back to Buffalo every bit of weather was in the exact same place we left it!

From Erie’s sunshine we hit flurries in Dunkirk. Over the course of a few miles the snow ramped up in intensity. It was snowing heavily as we passed through West Seneca then back to flurries by South Buffalo. I parked under cloudy skies back at our Gates Circle apartment where there was no sign any new snow had fallen.

That’s the power of Lake Effect snow: Persistence!

Lake Effect snow bands are often just a few miles wide, but within those few miles snowfall rates of 4 or 5 inches per hour are possible. The strength of cold air aloft and alignment of wind decides where the snow goes and its intensity. The wind needs a long ‘fetch’ over Lake Erie to be effective as a snow maker. That limits where Lake Effect snow can fall.

As long as the cold wind blows the snow can fall for hours or even days! A few miles often decides whether you get feet of snow or just a dusting.

There are only a handful of places in the world where this setup of cold air and properly aligned body of water exist. Buffalo and Syracuse just got lucky I guess.

Weather Too Good For June

Behind us the door to the deck is wide open and fresh air is blowing in. Birds are chirping. We hear their songs clearly because the air conditioning is off. This is very un-Junelike.

It’s Wednesday afternoon and Helaine and I are sitting in the family room with the Phillies on TV. Behind us the door to the deck is wide open and fresh air is blowing in. Birds are chirping. We hear their songs clearly because the air conditioning is off. This is very un-Junelike.

It’s currently 74&#176 with a dew point of 42&#176! If you’re meteorologically challenged that just means it’s cool and dry.

The observations come from my nearest reporting airport–Meriden. Weather Underground has a feature where I can look back on this date with one click of my mouse. It’s easy to quantify how unusual this is.

The Average High Temperature is 84 F with a historical range of 80 F to 91 F
The Average High Dew Point is 67 F with a historical range of 57 F to 73 F
The Average Low Dew Point is 57 F with a historical range of 47 F to 68 F

In weather nothing good lasts forever. This dry air will be gone by the weekend.

In the meantime today is sorta perfect… well except for the going to work part.

One Strange Weather Day

Through the evening broadcasts I kept a chance for thunder in and and sheepishly explained my reasoning. My bosses like me to be confident. It’s doubtful confidence was showing.

What a strange weather day. Nearly 100&#176 inland and mid-90s at the shore. Bradley broke a 45 year old temperature record early. Bridgeport set a record at 5:00 PM then broke it at 6:00! A little late in the day for record breaking warmth wouldn’t you say?

What was even stranger was the volatility of the atmosphere. For the past few days I’ve looked at the numbers and seen a powder keg. I use that analogy because powder kegs usually don’t explode, but they’re always potentially explosive.

Today was that kind of day. Last night I mentioned all we needed was a spark.

Meanwhile we motored through today with nary a cloud over Connecticut. As I prepared my forecast at 3:30 I considered taking the chance of thunderstorms out. I couldn’t do it.

I’m not sure I can explain what it was that kept me ‘on point.’ I suspect it’s experience at work. I’ve seen this kind of thing before… and been burned.

Through the evening broadcasts I kept a chance for thunder in and and sheepishly explained my reasoning. My bosses like me to be confident. It’s doubtful confidence was showing.

Then at 6:25 pm a lone cell popped up northeast of New London. It was tiny, but vicious. On the radar it went from green to deep red in under a mile. This was a cloudburst. In your car you’d see it ahead of you and drive directly into a wall of rain!

A few minutes later the Weather Service issued a severe thunderstorm warning for Southern New London County. Though the warning was valid until 7:15 it was quickly pulled as the cell collapsed into itself quashing the heavy rain.

It was the only thunderstorm cell that popped this afternoon. A towering cumulus cloud over Wallingford pictured at the top of this post (photo taken by Gil Simmons) never dropped its load.

Mostly what I do is objective. The same numbers produce the same results in my forecast.

Leaving the chance of thunder in was subjective. It was based on my knowledge of the area and formulated in such a complex manner I’m not sure how I knew to do it. I just did.