Tag: Storm Prediction Center

Weatherwise Tuesday Looks Bad Too

Storm Prediction Center May 20 2013 1730 UTC Day 2 Convective Outlook

This information is current as of Tuesday morning at midnight. When you look for a forecast, look for current information.

todayTerrible day today in the Southern Plains. 18 reported tornadoes. Around 100 reports of large hail. Nearly two dozen children killed at school. Thirty others dead as well.

The storms were well forecast. The area was warned. Some storms are beyond simple defenses.

Folks who live in Oklahoma hear warnings all the time. I suppose it’s easy to dismiss them and think, as has always been the case for most people, the storm will hit someone else. That was especially true because Monday’s severe weather set up in about the same place as Sunday–unusual.

mcd0741Tonight concern is centered from the Missouri bootheel through Eastern Illinois and Western Indiana plus a little corner of Kentucky and Tennessee. Tuesday it will be Northeast Texas (maybe the Dallas metroplex) into Northern Louisiana and Southern Arkansas under-the-gun.

Here’s the lead from the Storm Prediction Center’s tech discussion. Read what you can. I’ll follow with a translation to English.

CURRENT INDICATIONS ARE THAT PRE-FRONTAL CONVECTION DURING THE DAY 1 OVERNIGHT HOURS WILL RESULT IN OUTFLOW BOUNDARIES LOCATED WITHIN THE WARM SECTOR AT THE START OF THE PERIOD…AND THESE ARE EXPECTED TO PROVIDE AN ADDITIONAL FOCUS FOR SUBSEQUENT THUNDERSTORM REDEVELOPMENT DURING THE DIURNAL HEATING CYCLE ON TUESDAY.

A front is moving in from the west tonight. Thunderstorms will fire up ahead of it. Cold air, outflow from the storm, will pour down from the cloudtops.

The cold air will dislodge warm parcels near the ground which will keep the thunderstorm cycle alive.

Here in Connecticut we sometimes see storms refire from outflow, but there’s little skill in predicting which exact one. That’s why most watches and warnings you get from real people (like on TV) will talk more about general conditions than saying, “If you live on Flugle Street hit the basement now.”

We can nowcast these cells, not forecast them.

Tuesday in the Lower Midwest will be muggy. Overhead the jet stream will run a moderate speed, helping to draw parcels of humid air skyward from the surface.

ALTHOUGH LOW-LEVEL WINDS WILL GENERALLY BE AOB 20-25 KT…FORECAST SOUNDINGS INDICATE WINDS WILL INCREASE AND VEER WITH HEIGHT IN RESPONSE TO THE PROGRESSIVE SHORT WAVE TROUGH…PROVIDING SUFFICIENT VERTICAL SHEAR FOR ORGANIZED CONVECTIVE STRUCTURES INCLUDING A FEW SUPERCELLS TO DEVELOP. VERY LARGE HAIL…DAMAGING WIND GUSTS…AND POSSIBLY A FEW TORNADOES WILL BE POSSIBLE…ESPECIALLY WHERE BOUNDARY INTERACTIONS MAY ENHANCE LOW LEVEL SHEAR/SRH. ACTIVITY IS EXPECTED TO GROW UPSCALE BY EVENING WITH SEVERAL QLCS/S FORMING WHICH MAY RESULT IN AN INCREASE IN WIND DAMAGE POTENTIAL. ACTIVITY IS THEN EXPECTED TO WEAKEN GRADUALLY BY 03-6Z AS THE SHORT WAVE TROUGH LIFTS NEWD AWAY FROM THE REGION AND DIURNAL COOLING BEGINS TO STABILIZE THE BOUNDARY LAYER.

There won’t be much wind on the ground, but it will increase and change direction as it climbs. Wind shear is part of the formula for supercells.

The discussion mentions QLCSs, Quasi-Linear Convective Systems. These are storms which pack a line of damaging winds on the leading edge. Maybe you heard me mention “bow echoes” on TV? That’s part of the QLCS life cycle.

The worst times for storms will be Tuesday afternoon and evening with things finally simmering down before midnight.

Tornadoes are nasty. They often pack stronger winds than the strongest hurricanes. The whole concept of safety in a tornado is more relative than absolute. Tornadoes can grow stronger than any of our prep, as happened today.

I watched a man interviewed on CNN tonight. He carried all his worldly possesions in a laundry basket. He felt terrible for those who suffered more. He considered himself lucky tonight in Oklahoma.

I just can’t imagine.

I’m Expecting To Be Busy With The Weather

The Storm Prediction Center was we’re in the ‘slight risk’ area for severe weather today. Whereas most government warnings overstate the problem SPC’s are usually too conservative. A slight risk area nearly always leads to a Severe Thunderstorm Watch area. Conditions certainly favor that.

SPC’s usual pattern is to post the risk area then later discuss the area in more detail with a Mesoscale Discussion. The only MD in effect as I type is for Maine.

The Storm Prediction Center says we’re in the ‘slight risk’ area for severe weather today. Most government warnings overstate problems. SPC’s preliminary advice is usually too conservative. A slight risk area nearly always leads to a Severe Thunderstorm Watch area. Conditions certainly favor that.

SPC’s usual pattern is to post the risk area then later discuss the area in more detail with a Mesoscale Discussion. The only MD in effect as I type is for Maine. MDs lead with watches.

…MID ATLANTIC/NORTHEAST… A BREAK FROM THE RECENT HEAT IN THE EAST WILL EVENTUALLY COME IN THE FORM OF A WEAK COLD FRONT THAT WILL CROSS THE APPALACHIANS TODAY AND MOVE OFF THE MID ATLANTIC SEABOARD BY EARLY SATURDAY. A VERY MOIST AND INCREASINGLY UNSTABLE AIR MASS WILL PRECEDE THE FRONT THIS AFTERNOON WITH SBCAPE LIKELY TO EXCEED 2000 J/KG FROM NC TO NYC. TSTMS SHOULD BECOME MORE COMMON AS CONVECTIVE TEMPERATURES ARE BREACHED EARLY AND LIFT WITH THE FRONT AND UPPER TROUGH SPREADS EAST ACROSS THE SPINE OF THE APPALACHIANS.

If/When we get storms the largest threat will be downburst winds and, of course, the lightning itself! It’s a bigger deal because of all the outdoor graduation ceremonies scheduled. People and lightning don’t mix!

The good news is there’s more comfortable air on the other side and it should be in place by Saturday morning.

See you on the TV this afternoon. I’ll be wrangling the weather on the FoxCT News at 4.

Tracking The Tornado Outbreak

Tornadoes and large hail will be among the severe weather threats in the central and southern Plains on Saturday.


View Larger Map

I can’t remember a severe weather day with so much advance publicity. NOAA, the federal agency that responsible for the Weather Service and Storm Prediction Center has been relentless in scary press releases. I got another this morning.

Tornadoes and large hail will be among the severe weather threats in the central and southern Plains on Saturday. Experts with NOAA’s National Weather Service will provide a briefing to explain what’s expected and what’s causing the latest round of potentially destructive weather.

First things first. No one doubts these warnings are warranted. Kudos to SPC for getting ahead of the weather.

STATE AND LOCAL EMERGENCY MANAGERS ARE MONITORING THIS POTENTIALLY VERY DANGEROUS SITUATION. THOSE IN THE THREATENED AREA ARE URGED TO REVIEW SEVERE WEATHER SAFETY RULES AND TO LISTEN TO RADIO…TELEVISION…AND NOAA WEATHER RADIO FOR POSSIBLE WATCHES…WARNINGS…AND STATEMENTS LATER TODAY.

One Tornado Watch for Eastern Nebraska and Western Iowa already contained a spacial admonition.

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM NOON UNTIL 700 PM CDT.

…THIS IS A PARTICULARLY DANGEROUS SITUATION…

DESTRUCTIVE TORNADOES…LARGE HAIL TO 4 INCHES IN DIAMETER… THUNDERSTORM WIND GUSTS TO 70 MPH…AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

They’re called PDS watches–Particularly Dangerous Situation.

The best place to watch all this action is from the Storm Prediction Center‘s website. Everything will pass through there.

The biggest problem today is knowing tornadoes are coming is not enough. People can be sheltered, though some will not heed the warnings. For everything else all bets are off.

Note: The map at the top of this entry will update with live data until midnight, then will permanently contain data for 4/14/2012.

Where To Find Tornado Info

SPC’s site is a nerd’s delight! It is loaded with maps, charts and numbers. All the secrets are hidden in plain sight if you know where to look.

From the Ohio Valley south this is an explosive night! Over 50 tornado touchdowns have been reported so far and the day is far from over. There is a continuous line of Tornado Watches from Central Ohio to the Florida Panhandle!

I sent texts to two friends in the Nashville area. I told them the storms near them deserve respect. They get it.

If you’re interested in severe weather the best place to go is the Storm Prediction Center‘s own site. Severe weather forecasting has benefited from digital technology and instant communications more than any other forecast discipline.

SPC’s site is a nerd’s delight! It is loaded with maps, charts and numbers. All the secrets are hidden in plain sight if you know where to look.

The SPC homepage is built around a map with rollover menu. No clicking necessary. Just mosue from menu item to menu item to see the map instantly populated with data.

Clicking the mesoanalysis tab opens another map with the country divided into zones. Some zones are fixed by geography. Others float in response to current or soon-to-be-current conditions. Each can be filled with the parameters most useful in predicting severe storms.

As the weather progresses and new storms look likely SPC issues Mesoscale Discussions. In these discussions forecasters lay out their thinking behind the watches to come. These are often very technical and cloaked in arcane terminology and even more obscure abbreviations.

I’ve been doing this nearly 30 years and I still scratch my head from time-to-time!

SUPERCELLS MOVING THROUGH ERN KY WILL CONTINUE THROUGH AN ENVIRONMENT VERY FAVORABLE FOR STRONG TO VIOLENT TORNADOES AS THE LLJ STRENGTHENS TO IN EXCESS OF 60 KT. LAST VWP DATA FROM JACKSON KY INDICATE VERY LARGE 0-1 KM HODOGRAPHS WITH STORM RELATIVE HELICITY ON THE ORDER OF 800 M2/S2 AND 500 J/KG MLCAPE. THESE PARAMETERS ALONG WITH THE DISCRETE NATURE OF THE CONVECTION WILL CONTINUE TO PROMOTE A THREAT OF TORNADOES…VERY LARGE HAIL AND DAMAGING WIND NEXT FEW HOURS.

That one I understood entirely.

SPC is also the keeper of the storm reports. What’s listed is often unverified and subject to revision, but still a good indicator of what’s going on. There are over 300 reports today including tornadoes!

When tornadoes are on the ground or severe storms are spotted the responsibility gets moved to local Weather Service offices. Following details becomes more random and difficult since offices cover oddly shaped areas. The Storm Prediction Center still watches, but with more of a hands off attitude.

If this site would have existed when I was growing up I might have never left the house!

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.

Something I Didn’t Know About The Tornado Numbers

A change of methodology means tornado reports are inflated when compared to prior years.

I was reading Reddit when I came upon this. A change in methodology means tornado reports are inflated when compared to prior years.

[T]he NWS changed its policy regarding duplicate severe weather reports this year.

It should be noted that duplicate preliminary reports are NO LONGER purged from the data set. As a consequence, it is not possible to compare this preliminary data to previous years’ data. In the past, possible duplicate reports were culled based on time and proximity. This is not the case anymore.

The old rule of thumb was ~15% of preliminary reports were duplicates. Based on the preliminary v. final numbers so far this season it is possible that up to 65% of these preliminary reports are duplicates.

On March 8, 2011, the SPC removed space/time filtering on incoming National Weather Service (NWS) Local Storm Reports (LSRs). This filtering had been used by SPC in an attempt to reduce duplicate reports and limit artificially inflated initial estimates of severe weather events when many reports arrived for the same event. Space/time filtering is no longer being applied to decoded NWS LSRs and this approach is consistent with NWS storm-based verification methods.

You probably already know the number of weak tornadoes reported has gone up over time as ‘chasing’ has made fewer of them unobserved.

Tornado Prediction From The Experts

Like a hot air balloon as long as the parcels remain warmer than their surroundings they’ll continue to rise. As described by SPC the Midwest has an added feature this weekend–the jet!

There’s a big severe weather outbreak still underway this weekend. At least one Iowa town was flattened yesterday with 31 tornadoes reported overall. Today it’s ‘only’ six. The evening is young. Three Four tornado watches and one severe thunderstorm watch are up as I type.

The prevailing wisdom is tornadoes form during a clash between warm moist and cool dry air. That’s a situation likely to exist in the Midwest every spring.

However, if you listen to the experts from the Storm Prediction Center you’ll see there’s more. Tech stuff first. I’ll translate after you read it.

SCATTERED VIGOROUS STORMS ARE ONGOING…FROM NEAR THE DEEP SURFACE CYCLONE CENTER MIGRATING ACROSS NORTHWEST WISCONSIN…SOUTHWARD TO THE VICINITY OF A 90 KT SOUTHWESTERLY 500 MB JET AXIS ACROSS SOUTHWEST WISCONSIN. AN EMBEDDED SPEED MAXIMUM IS IN THE PROCESS OF NOSING ACROSS THE UPPER MISSISSIPPI VALLEY TOWARD THE UPPER GREAT LAKES REGION…WITH A REGION OF ENHANCED UPPER DIVERGENCE CONTRIBUTING TO CONVECTIVE DEVELOPMENT.

  • Deep surface cyclone is a low pressure system at ground level.
  • 90 kt southwesterly 500mb jet axis means there’s a wind blowing between 110-115 mph at approximately 18,000 feet. The exact height isn’t important.
  • Enhanced upper divergence means as the wind is moving by it’s spreading out.
  • Convective development means thunderstorms born of air moving upward in the atmosphere

These conditions paint a serious situation because of how thunderstorms form and what make them strong (sometimes strong enough to spawn tornadoes).

In a thunderstorm parcels of relatively warm air rise into a colder atmosphere. Like a hot air balloon as long as the parcels remain warmer than their surroundings they’ll continue to rise. As described by SPC the Midwest has an added feature this weekend–the jet!

A strong jet streak will help rising air ascend even faster and make the situation much more volatile. Divergence means additional air will need to be sucked up from below to fill an increasingly large atmospheric void. It’s a scary and vicious cycle.

The good news is this severe weather is exceptionally well forecast. It’s tough to believe anyone in the bullseye doesn’t know what’s going on.

The bad news is sometimes there’s just nowhere to hide.

Why No Watch?

A watch is supposed to be the ‘heads up’ before bad weather strikes.

See note at the bottom of this entry for additional information received since I first posted.

I am surprised there was no severe weather watch for New York City, Connecticut or the surrounding environs this afternoon. Without a watch Staten Island, Brooklyn and Queens went directly to a Tornado Warning just as parts of Connecticut have just gone to a Severe Thunderstorm Warning (since cancelled).

A watch is supposed to be the ‘heads up’ before bad weather strikes.

A Severe Thunderstorm Watch will be issued when conditions are favorable for development of severe thunderstorms. While not anticipated, tornadoes may occur in the watch area. The Storms Prediction Center (SPC) is the sole agency responsible for issuing a watch. A watch covers several thousands of square miles and generally lasts from two to six hours.

I’m not sure yet if there’s been anything more than heavy rain so far in Connecticut but photos and video from New York City show lots of damage. The photo at the top of this entry is unverified so take it with a grain of salt, but it’s a powerful image. (I now have additional info on the photo. See below.)

Everyone expected strong storms. You didn’t have to be a forecasting genius to see that. That makes the absence of a watch even more troubling.

Sometimes I’m just as puzzled by this stuff as you.

Note: After posting this Huffington Post found the image is true but not from Thursday. There was a great deal of damage in Queens and Brooklyn Thursday, but so far no official confirmation of a tornado. I suspect evidence will prove there was one.

Tornado and Severe Weather Damage

A scary day across the Midwestern US with over 40 tornadoes reported, plus hail and damaging wind. The Storm Prediction Center tracks this stuff on an hourly basis (as well as making predictions). A site well worth seeing, especially today.

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Storm Prediction Center Gets Scared

I usually take a casual look at the maps from the Storm Prediction Center. In this day of weather specialization, these guys watch for severe thunderstorms and tornadoes.

In the past I have been critical of their work in the Northeast where severe weather responds to different stimuli than in the Plains. They do a good job in giving people like me a ‘heads up.’ We’re much better off with them, than without them. More flexibility in issuing watches here would be helpful.

I’ve watched with great interest over the past few days as they’ve posted a high risk outlook for severe weather over a large area. ‘High risk’ and ‘large area’ are rare and usually mutually exclusive.

ZCZC SPCPWOSPC ALL

WOUS40 KWNS 151652

ARZ000-ILZ000-INZ000-KYZ000-MOZ000-MSZ000-OHZ000-TNZ000-160045-

PUBLIC SEVERE WEATHER OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

1052 AM CST TUE NOV 15 2005

VALID 151652Z - 160045Z

...OUTBREAK OF SEVERE THUNDERSTORMS EXPECTED OVER PARTS OF THE

OHIO...TENNESSEE AND LOWER MISSISSIPPI VALLEYS LATER TODAY AND

TONIGHT.

THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE

DEVELOPMENT OF A FEW STRONG...LONG-TRACK TORNADOES OVER PARTS OF THE

OHIO...TENNESSEE AND LOWER MISSISSIPPI VALLEYS LATER TODAY AND

TONIGHT.

THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE

CENTRAL AND EASTERN ARKANSAS

SOUTHERN AND EASTERN ILLINOIS

MUCH OF INDIANA

WESTERN AND CENTRAL KENTUCKY

SOUTHEAST MISSOURI

NORTHERN AND CENTRAL MISSISSIPPI

WESTERN OHIO

WESTERN AND MIDDLE TENNESSEE

SURROUNDING THE HIGH RISK AREA...THERE IS A MODERATE RISK OF SEVERE

THUNDERSTORMS FROM SOUTHERN LOWER MICHIGAN INTO LOUISIANA...SOUTHERN

MISSISSIPPI AND WESTERN ALABAMA

A WIDESPREAD AREA OF SEVERE THUNDERSTORMS...INCLUDING SOME WITH

LONG-TRACK TORNADOES AND VERY DAMAGING WIND...WILL AFFECT A LARGE

PART OF THE EAST CENTRAL U.S. LATER TODAY THROUGH WEDNESDAY MORNING.

The operative words are “strong” and “long track.” That’s the recipe for disaster.

So far, there’s been one report of 65+ knot wind in Southwest Missouri. The day is young.

This weather system gets to us in Connecticut tomorrow. To quote Dorothy, “We’re not in Kansas anymore.” There will probably be storms, just not as intense or with as much damage.

Meanwhile, if I were in the bullseye on the SPC map, I’d be sweating bullets today. Someone’s going to get hurt, or worse.

Significant Weather Night

It was a busy afternoon at work. The Storm Prediction Center issued a Severe Thunderstorm Watch a little after 1:00 PM. They weren’t kidding.

As the afternoon progressed and the storms moved in, the watch turned into a series of warnings. At one point I decided it was futile to separate them and just told everyone to get inside and wait the weather out.

You know the old phrase, “It never rains, it pours?” That is so true with my work. The workload on a day like this increases exponentially. There’s so much information coming out, I don’t think viewers can absorb it all. So, you simplify a little in order to make points everyone will understand.

My friend Peter had it worse than me. He was scheduled to leave Philadelphia tonight, heading to France. In order to upgrade and get a larger seat, he was flying Philadelphia – Washington – Frankfurt – Nice. Ouch!

On his way to Philadelphia International he got a call telling him his flight to IAD was canceled!

He had hired a car to drive him to the airport which then turned south, heading to the Washington suburbs. I don’t want to think about how much this drive will cost – this is a very long trip. There’s not a chance United will absorb any of his cost.

We spoke a few minutes ago as he approached the terminal. He’ll make the flight, but this is going to be a very long night for him.

Meanwhile, here in Connecticut, the severe weather has moved on – thankfully.

Google Maps And Severe Weather

By now I hope you’ve seen Google’s map application. To me, it’s better than all the others for maps and directions.

Part of what makes Google’s mapping cool is Ajax coding, something I’m about to talk about, though I really don’t understand it. It’s a method which allows the Google page to appear ‘live’. You can drag a map and scroll it across the page as if it lived on your PC and not Google’s servers.

Like I said, it’s really cool.

Part of the ‘fun’ of applications like this is the ability to ‘hack’ them. I’m not talking about stealing credit card numbers. ‘Hack’ here is used in its purest geek sense of modifying and extending someone else’s work.

A perfect example is Storm Report Map. This online application takes the daily severe weather reports from the Storm Prediction Center and navigates them on Google’s maps.

This is very impressive stuff. There’s gotta be more to come!

Hurricane Questions

After the loss of life, and confusion, following Hurricane Charley, an interesting op-ed piece was written by Bryan Norcross, Chief Meteorologist from WFOR in Miami. You can read it here now, or click the ‘continue’ link at the end of this posting.

Norcross makes some interesting points, many of which I agree with.

Though we make our own forecasts at the TV station, we respect the Weather Service’s watches and warnings (though there are times I mention them, followed by what I think will actually happen).

The bigger problem occurs when watches and warnings are contradictory. Uncoordinated watches, warnings and statements for hurricanes, severe storms… even winter weather, is a continuing weakness of The Weather Service. All hurricane watches, warnings and statements should come from one place – period.

This certainly led to the disservice done to the people for Florida.

When local offices speak, they address problems from their own perspective, which is not necessarily the public’s. And, the public and media are probably concentrating their attention on the Storm Prediction Center (Whose idea was it to change this from the much more meaningful Hurricane Center?), which is where most people would expect to find hurricane info.

I work in Connecticut, a small state served by three NWS offices. Their statements often mislead the public because each only refers to the region for which they forecast.

Here’s an example. If Boston says a watch has been canceled for Connecticut, they mean their counties. No one in Connecticut could read a statement like that and understand that half the state is still under a watch.

During the winter, Litchfield County, our ‘snowbelt,’ might be under a lesser category of alert because the Albany office uses somewhat different criteria than the New York or Boston offices. When I post a map which shows a Winter Weather Advisory for Litchfield while there’s a Winter Storm Warning for our other counties (even though Litchfield has the more wintry forecast) it does nothing but confuse.

I have been to NWS ‘customer’ conferences in Washington, and have tried to sensitize them to this confusion. As you see – no change.

Continue reading “Hurricane Questions”

Another Slashdot Submission

My luck with Slashdot has not been good recently. I had a bunch of my earliest submissions accepted and began to think it was easy to get on. No such luck. Since February I have had 15 in a row rejected.

I really don’t want to give up, because Slashdot, like no other website, is ‘geek confirmation.’

Today, I tried again. Since (judging by my track record) it probably won’t get on, I thought I’d post it here too. The links are worth clicking.

For most of the United States (sorry West Coast), this is the season for lightning. It is as powerful as it is spectacular to look at. It is destructive too – by itself or through the hail, straight line winds and tornadoes that often accompany it. As someone who forecasts the weather, I’m often asked about lightning. As you might imagine, there’s plenty to see about lightning on the Internet. The conditions necessary and a little bit of the physics behind lightning are explained by Jeff Haby, a meteorologist (one of my professors actually) at Mississippi State University. Once forecasters get a handle on what’s going on, they put the word out through the Storm Prediction Center. Regular outlooks are issued by SPC for severe storms. Once those storms rear their ugly heads, they’re followed with mesoscale discussions looking at the active areas. The Storm Prediction Center is also the place where Severe Thunderstorm and Tornado Watches are issued and storm related damage reports are compiled. Lots of hobbyists like to track lightning strikes on their own, and there’s equipment available to do just that. Getting hit by lightning is never fun, though not always fatal. National Geographic chronicled an amazing story of a lightning strike, and rescue, on Grand Teton.