National Weather Service, NOAA

Pittsburgh, PA

Spring/Summer 2007



Due to circumstances beyond our control (health issues), we had to reduce the number of SKYWARN classes this spring. However, I was still able to conduct 13 classes with about 480 total attendees. Thanks to all of you for your support, help and understanding this spring. We will probably conduct some classes this fall and I will start soliciting particular counties about mid-summer. We also had our "first ever" Advanced SKYWARN training class held at California University. The reviews seemed rather good. The class is much more rigorous than the basic course and covers some pretty intense subjects such as: Shear, Buoyancy, the hodograph, the Skew-T Log p chart, radar principles and more. We may offer a class or two next time around but anyone desiring to take the advanced class should take the basic class as a prerequisite. Remember, the advanced class is not for beginners and covers some very heavy duty material.



The National Oceanic and Atmospheric Administration (NOAA) predicts 13 to 17 named storms this year with 7 to 10 becoming hurricanes. Three to 5 could become major hurricanes of Category 3 strength or greater. We are forecasting that there is at least a 75% chance of above normal tropical activity. A normal hurricane season brings 11 named storms, with 6 becoming hurricanes and two attaining major status.

Reasons for the above average year include the following: a continuation of the ongoing multi-decadal signal (the set of ocean and atmospheric conditions that spawn increased Atlantic hurricane activity), warmer-than-normal sea surface temperatures in the Atlantic Ocean, and a La Nina episode. Remember last year when all forecasts also touted an above normal year and they all proved to be too high. The largest factor diminishing the number and strength of Atlantic Hurricanes was El Nino. Typically, in an El Nino event, the winds high in the atmospheric above the equatorial Atlantic tend to be rather strong. This has a tendency to rip hurricanes apart and actually be a hostile environment for hurricane formation. On the other hand, La Nina tends to be associated with more tranquil high level winds which favor hurricane development. The Atlantic hurricane season runs from June 1 through November 30.


The National Weather Service (NWS) instituted the EF Scale for tornadoes on February 1st. The EF Scale allows for a more detailed analysis and better correlation between damage and wind speed.

Original Fujita Scale____________________________Enhanced Fujita Scale

F0 . . . .40-72 mph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .EF0 . . .65-85 mph

F1 . . . .73-112 mph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .EF1 . . .86-110 mph

F2 . . . .113-157 mph . . . . . . . . . . . . . . . . . . . . . . . . . . . . .EF2 . . .111-135 mph

F3 . . . .158-206 mph . . . . . . . . . . . . . . . . . . . . . . . . . . . . .EF3 . . .136-165 mph

F4 . . . .207-318 mph . . . . . . . . . . . . . . . . . . . . . . . . . . . . .EF4 . . .166-200 mph

F5 . . . .261-318 mph . . . . . . . . . . . . . . . . . . . . . . . . . . . . .EF5 . . . >200 mph



We had our first EF tornado this spring on May 1st. About 6:15 PM an EF0 tornado touched down in Mercer County, Pennsylvania. There was a sporadic damage path about 4 miles in length. The maximum width was about 100 yards and the estimated maximum winds were about 75 mph. (For more information on the EF Scale see


Over the past 10 years our County Warning Area (CWA) has averaged 4 to 5 tornadoes per year. Last year (2006), there were two confirmed tornadoes. One occurred on June 22nd in Tuscarawas County, Ohio (F1) and the other in Westmoreland County, Pennsylvania (F1) on December 1st.



If anyone notices that one of our NWR transmitters is experiencing a problem, we would appreciate a call. You can use the SKYWARN number.



On May 10th, 2007, Westmoreland County became the 10th county in the county warning area of NWS Pittsburgh to be recognized as StormReady. The other counties/major city include: Allegheny County, PA, The City of Pittsburgh, Fayette County, PA, Mercer County, PA, Monongalia County, WV, Ohio County, WV, Preston County, WV, Venango County, PA, Washington County, PA.



E-SPOTTER is an Internet based program which allows spotters to send in reports directly to the NWS office. We have activated the program for the NWS Pittsburgh office. If you are a trained SKYWARN spotter for the Pittsburgh NWS office, you can register at You can then fill out either the Severe Weather Report Form or Winter Weather Report Form online and submit them to us in near real-time. If you remain logged into E-SPOTTER, once we acknowledge your report, you will get an indication that your report has been received on the screen. Please try to concentrate on those reporting items that we stress in the SKYWARN class (also contained in this newsletter).

There will be times when we cannot respond to your reports immediately because of workload or warning priorities. If you think your report is critical and very time sensitive, call us on the toll-free number. Please do not send an E-SPOTTER report via the Internet and then follow-up with a telephone call. This will actually double our workload.



It's a great way for SKYWARNers in the Pittsburgh CWA to stay connected, share information, discuss the weather, share files and pictures, and more! To join, just visit



NWS Pittsburgh SKYWARNers who live in Pennsylvania please see the letter below:

FROST - a year-round experience in Pennsylvania!

Pennsylvania State Climate Office has initiated a new observation program known as FROST (Frost, Rain, Optics, Snow and Thunder). This program will be composed of a network of volunteers who will take daily observations and document significant weather events. These observations will be recorded through an easy-to-use web based entry form. We are specifically looking for individuals not already in a weather network.
            Our goal is to gather the data from as many parts of
Pennsylvania as we can find, especially in lesser populated areas. This data will be collected, assessed and displayed in an easily accessible format on the CoCoRaHS website which can be found at
            Each volunteer is requested to record data in the following categories: Daily Rain, Intense Rain, Number of Thunder Claps, Daily Snow, Snowflake Shape, Optical Effects and occurrences of frost. Volunteers receive online training with instructions and an occasional training seminar offered in specified locations in the state. Each volunteer will receive a packet with instructions on instrument siting and measurement techniques. The FROST web site is at All new volunteers will find reporting and data entry procedures on the CoCoRaHS website.
            Since the program has just begun, the PA Climate Office is still in the process of recruiting volunteers. Each volunteer will be providing valuable information that will be used to expand our climatological record as well as verify daily forecasts.  We are expecting to award the first dozen volunteers from NWS contacts a free rain gauge! So, please spread the word to help out your state climate office.  Email today if you have any questions.
The PA State Climate Office



Currently, the NWS issues warnings for entire counties. However, as of October 1st, 2007, we will switch from county-based warnings to storm-based warnings. This means that we will issue discrete polygons (or boxes) which will cover a specific area. We will no longer be concerned with political boundaries (county boundaries) but rather, the area which will be impacted by the particular severe thunderstorm cell. Experimentation at several NWS offices has indicated that the total area warned was reduced by 73%. Additionally, the number of towns warned were reduced by 70%. This will be a significant change in the way we warn for severe weather. At the same time, it will even increase the importance of SKYWARN reports. We will be searching for verification in each warning polygon.



Lightning has killed at least 8 people in the U.S. since March 1st, 2007. In an average year, lightning kills more people than tornadoes and hurricanes combined. Almost all lightning-related casualties can be prevented through education and personal responsibility. Many people are simply not aware of the lightning safety rules and unknowingly put themselves (or their family) in danger. Check out much more about lightning safety at



Our long range summer forecast calls for a better than average chance of above normal temperatures for June, July and August. Meanwhile, we have equal chances of seeing above or below normal precipitation. These same trends continue into the fall (September, October, and November). (see the Climate Predictions Centers web site at



As many of you are aware, the forecasters at the PBZ WFO office rely on the Skywarn program to provide accurate severe weather reports from around the county warning area by trained Skywarn Observers. The information you pass along to the office has an immediate impact on the warning team which leads to better situational awareness. One function of the Skywarn program is to provide ground truth to our radar algorithms, and it aids tremendously in providing us critical information that we use in our warning decision process (i.e., whether or not to warn for the next downstream county). The method which we use to issue a warning is based on three steps. First, we conduct an analysis of current conditions upstream of our area, and whether the forecast conditions tracking across the region could warrant issuing a watch and later a warning if needed. Second, as we get closer to the event we start with a mesoscale analysis and factor in vital information from the radar and satellite data. Third, spotters start reporting in key information relating current conditions for their location. From your reports, forecasters operating the radar become better aware of the potential of the thunderstorms and can directly apply this important information to our decision making process for more timely and accurate warnings.

In order for the forecaster to make an informed decision about current conditions, it is critical that the weather elements reported are as accurate as possible. Spotter reports may differ from the radar data which is critical to the decision making process. Timeliness is one of the most important factors that the forecaster will face, so the reliability and accurateness of the information passed along by the spotter is a serious matter. The difference for the forecaster operating the radar and hearing a spotter report with "probably or maybe pea size hail" vs. measured with a ruler pea size hail "is like night and day." The confidence of the forecaster will increase exponentially with accurate or measured data to compare with radar signatures.

In addition to the most common visual weather elements reported to us by our spotters, a growing number of you are adding your personal off-the-shelf-technology weather equipment into the mix. The National Weather Service and the Citizen Weather Observer Program (CWOP) are working together to be able to ingest your data directly into our network of current conditions (surface observations) reported and updated at 5 and 15 minute intervals. The number of weather elements in these reports has significantly contributed to our overall situational awareness of the atmosphere. 

If you have a well-sited weather station at your location and youre interested in providing accurate data for our use, then we would like to help you get started. The first step would be to log-on to the CWOP web site. There is a wealth of information on the program and step-by-step instructions on how to sign-up for the program.




Try to report as soon as possible after observing the event and, remember to be careful! Also, if possible, please give us your location relative to the closest city or town as well as, your county. (For example, Fayette County, about 3 miles southeast of Uniontown).

SNOWFALL - After 2 inches of new snow, and then at 4 inches, 6 inches, and every 3 inches thereafter (e.g., 2, 4, 6, 9, 12, etc.)

FREEZING RAIN - As soon as you observe the occurrence of freezing rain or freezing drizzle, especially if it starts to collect on objects. Call again if the glaze/ice accumulation exceeds 1/4 inch

THUNDER SNOW - Location and time of occurrence

WIND SPEEDS - Report wind speeds greater than 40 mph

RAINFALL - Report any rainfall in excess of 3/4 inch in an hour

FUNNEL CLOUD - A "rotating" appendage descending from the base of a cumulonimbus cloud, but not touching the ground. If possible, always look at the area beneath the funnel cloud for flying debris. If flying debris is observed, it is a tornado.

TORNADO - Violently rotating column of air descending from a cumulonimbus cloud and touching the ground. Look for flying debris. If possible, report any injuries or fatalities. Tornadoes usually rotate counterclockwise, and this can be a good indicator if what you are observing is a tornado or other meteorological phenomena. However, this is not always true. When it doubt, report!

HAIL - Report any size hail. Specify the diameter based on the hail scale (coins)

FLOODING - Report any flooding you observe, including basement, road, stream, creek, and ice jam flooding. Report the name of the stream/creek, road number/name (if applicable) and depth

DAMAGE - Report all storm-related damage (large branches, fallen trees, structural damage, flood damage, etc.) Even if it is several days after the event.




In case you didnt get these web sites in SKYWARN class:


E-mail =

NWS Pittsburgh =

NOAA Weather Radio =

Storm Prediction Center =

Heavy Precipitation Center =

NWS/NOAA Online Weather School =

AHPS River Flood monitoring =

Basic SKYWARN brochure (for downloading) =

Advanced SKYWARN brochure (for downloading) =


Also, remember that we have a 5-year recertification. We would like all of our SKYWARNers to attend a class at least once every 5 years.




All SKYWARNers have our toll free number. In addition, you are welcome to call the number that appears on our warnings (1-877-633-6772). When you dial this number, you will not talk to a forecaster, but rather, it will direct you through a menu for reporting your specific severe weather type. Many times, I think spotters may be reluctant to call because you may think you are bothering us. This method will give you another choice in which you will not have to talk to a person, but rather just use the telephone menu. In the future, we hope to implement an option that designates you as a trained SKYWARN spotter.




The NWS attended the Breezeshooters Hamfest in Butler on June 4th. It was good to see all of you.


Our New 6 meter radio

The NWS has a new 6-meter radio thanks to Paul (NC8W). The repeater frequency is 51.640 with a negative 500 KHz split. The PL for the Cross Creek receiver is 127.3. This radio will probably best serve some of our Ohio counties and possibly Mercer in Pennsylvania. Alan (KB3DHC) mentioned that a "voting receiver" may be installed soon which will simplify things.


Another New Radio Possible for WX3PIT

We've requested a Kenwood TS-570DG HF radio and associated antenna. It's unclear whether we will get it, but we're hopeful.


The National Weather Service in Pittsburgh would like to extend a thank you to all of the amateur radio operators across our county warning area. In addition, a special thank you goes to all who volunteer their time at the forecast office (WX3PIT).


We would also like to thank each county in our County Warning Area (CWA) for their participation in the Amateur Radio SKYWARN program. It is sometimes difficult to get an amateur radio operator to staff the station at the National Weather Service. This sometimes results in frustration and the need for Net Control Stations to report via the SKYWARN Reporting Number. Your patience and assistance is greatly appreciated.



The National Weather Service would also like to extend a thank you to all of our SKYWARN members. Your reports save lives! We appreciate your participation and support.

Thanks also to the members of the NWS Pittsburgh staff who contributed to this newsletter.