One of the main challenges a meteorologist faces (and this is true for many professions. I eagerly await a post from Matt Simmons drawing a parallel in systems administration) is effectively getting a message to the public. This becomes especially important in times of severe weather when the timeliness and clarity of the message can literally be the difference between life and death. While the National Weather Service and the media do a good job, there’s a lot of room for improvement. Let’s consider the three questions a person needs answered:
- Am I threatened?
- If so, what do I do about it?
- When am I in the clear?
Now compare this to an actual warning.
WUUS53 KIND 011733
BULLETIN – IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
133 PM EDT SUN JUL 1 2012
This is just header information. The public rarely encounters it directly.
THE NATIONAL WEATHER SERVICE IN INDIANAPOLIS HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR…
CARROLL COUNTY IN NORTH CENTRAL INDIANA…
NORTHWESTERN CLINTON COUNTY IN CENTRAL INDIANA…
NORTHEASTERN TIPPECANOE COUNTY IN WEST CENTRAL INDIANA…
Okay, so let’s assume I know what county I’m in. Am I in the right part of the county?
* UNTIL 230 PM EDT
The first question to be definitively answered is the third one.
* AT 131 PM EDT…NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL…AND
DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED 6 MILES
SOUTHEAST OF BROOKSTON…OR 8 MILES NORTHEAST OF LAFAYETTE…AND
MOVING EAST AT 40 MPH.
There’s some town names here and a description of the threat. Maybe I can figure out if I’m threatened by this or not.
* LOCATIONS IMPACTED INCLUDE…
THIS INCLUDES INTERSTATE 65 BETWEEN MILE MARKERS 173 AND 181.
Oh, okay! My city isn’t listed, so I’m probably in the clear. Folks in Delphi know that they are threatened. The first question is answered.
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR…DESTRUCTIVE HAIL…DEADLY LIGHTNING…AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.
TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM…AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
And here, basically at the end of the warning, is the answer to question 2.
LAT…LON 4073 8652 4070 8652 4069 8637 4063 8636
4034 8641 4045 8693 4057 8689 4057 8678
4066 8678 4067 8676 4073 8676 4074 8675
TIME…MOT…LOC 1733Z 280DEG 19KT 4052 8679
WIND…HAIL 60MPH 1.00IN
The latitude/longitude pairs define the shape of the warning (more on that in a bit). This can be used to provide really good answers to question 1.
Your typical severe weather warning answers all three of the questions we base our discussion on, but in the wrong order. Arguably, question 1 gets answered first, although it relies greatly on the geographical awareness of the public. I suspect many adults are aware of what county they live in (due to school districts, libraries, property taxes, etc), but if they work in a different county, do they know that county’s name? Can they name the surrounding counties (this is useful for preparedness. If the county to your west is under a warning, chances are good you might be soon)? The fact that subsections of counties (e.g. “northeastern Tippecanoe County”) are variable and undefined only add to the confusion.
The fact that the “call to action statement” (what NWS meteorologists call the answer to question 3) comes at the tail end of the warning means that a full minute may pass until it’s made clear what actions someone should take. In many cases, the lead time is sufficient that this additional time is acceptable, but in short-lead-time situations (for example, the Joplin, MO tornado of 2011) every second counts.
It’s not bad to give people more information than they need, especially when it reinforces your point. One example comes from a derecho that hit Louisville, KY on July 13, 2004. This storm caused widespread damage through southern Indiana and central Kentucky. In order to make it clear that this was an exceptionally dangerous storm, one of the forecasters at the NWS office in Louisville made mention of “hurricane force winds” in the warnings. Although this wasn’t strictly necessary, it helped to make the danger more clear in the mind of the public. Extra information can be valuable, but it should never get in the way of the main point.
So how would I re-format warnings?
THE NATIONAL WEATHER SERVICE HAS ISSUED A <threat> WARNING FOR
<counties>, including <cities>
<call to action, don’t die, etc.>
<THIS WARNING EXPIRES AT <expiration time>
<More explanation, supporting info>
The media has an advantage here, as they can format their presentation of the warning however they’d like. The NWS is stuck with a defined format. It’s worth noting that decades ago, the public did not receive NWS products directly; they were filtered through the broadcast media first. In modern times, All-Hazards Radio, weather websites, and mobile apps are putting more NWS products directly in front of the public. So far, the NWS has not updated warning text to fit this new model.
One thing you may have noticed is that my version doesn’t mention the office issuing the warning. I had this discussion with a recent meteorology graduate last week. What use is knowing what office issued the warning? Most people probably don’t know what NWS office serves them. Furthermore, a warning may be issued by a backup office if the primary office is unavailable (e.g. if the office staff is taking shelter because they’re about to get hit by a tornado). Adding the issuing office does nothing to answer or reinforce the three questions. It’s not extra information, it’s extraneous.
Note: I was going to add some comments about the shape of warnings, but this post is long enough and that rant won’t be short. Look for it in the next few days.