National Weather Service Forecast Office

Welcome the National Weather Service Wilmington North Carolina on-line spotter training. We are always looking for trained spotters to help with verificaton of severe weather events. If you are interested in joining our team of spotters... please take time to read through the training. To view the sections...just click on the links to the left. At the end of the training there is an online quiz available. If you obtain a score of 70 percent or better...you can print out a certificate of completion.

Office
Overview of office

NWS Mission
Mission Statement

Skywarn Spotters
Your Role

Warning Process
Outlook Watch Warning

Warning Process
Time Scales

Thunderstorm Dangers
Flooding...hail...etc...

Flooding
Statistics

Reporting Flooding
General Guidelines

Hail
By the numbers

Hail Damage
Florence SC damage

Reporting Large Hail
Basic Guidelines

Reporting Large Hail Second
Specific sizes

Estimating Wind Speeds
Guidelines

Microburst
Formation/Impact

Microburst Second
Rain Foot

Microburst Third
Microburst Damage

Welcome to The National Weather Service in Wilmington. We are a small federal government agency with a staff of 23. The office operates 24 hours a day...seven days a week.

Our mission is to provide weather...hydrologic...climate forecasts and warnings for the United States...its territories...adjacent waters and ocean areas for the protection of life and property...and the enhancement of the national economy.

Trained spotters play a vital role in helping us fullfill our mission. They provide ground truth that aids in the warning decision...adds value to the warning or statement. This in turn can help motivate people in the path of the storm to take shelter.

In most cases the warning process begins a day to three days out with an outlook. The next step is a watch...which is basically a heads-up that severe weather is possible during the next few hours. The final step is a warning...which means severe weather is occurring.

The warning process is also based on spatial scales. The outlook generally covers the largest area. The watch generally focuses on a smaller area. A warning is usually the size or a county or even a couple of counties.

There are many thunderstorm dangers to discuss: hail...flooding...lightning...damaging wind...and tornadoes. We experience an abundance of these elemtnts in North and South Carolina.

Statistically...flooding is the number one thunderstorm related killer. With relatively flat terrain and poor drainage...Southeastern North Carolina and Northeastern South Carolina are prone to flooding events. Slow moving thunderstorms...tropical systems and coastal storms are the main causes of flooding in our region.

a picture of what to report with flooding

When reporting flooding...please be ready to give an estimate of the depth of the water based on known objects. Also tell us if the water standing or flowing? Are the roads closed or impassable. Also...does this area tend to flood frequently?

We also see our fair share of hail in the region. As the graphic shows...hail can cause a lot of damage to property and crops. Most of the hail that falls in our area is small...around pea size which is about a quarter of an inch in diameter. We do get some larger hail from time to time as the next image shows.

Hail damage in Florence South Carolina. This hail was reported to be the size of softballs and grapefruit.

Some things to remember about reporting hail are:
Report any hail...this can be very important to forecasters.
Let us know if the hail is covering the ground.
Let us know when the hail fell and tell us if it is currently falling.
Report the hail size in reference to coins and balls...go to the next slide to get a reference chart.

The most important part of reporting hail is the size. You can print out the following hail size reference chart for reference. Most of the sizes can be compared to coins and sports balls.
Do not report hail in reference to marbles! There are many sizes of marbles and this can be confusing.

a picture of what to report when reporting wind speeds

Almost all thunderstorms are accompanied by strong winds. It takes a lot of practice and experience to estimate wind speeds. On this chart are some general guidelines for estimating wind speeds. The following couple of slides will detail some of the features associated with strong winds.

By definition a microburst is:
A convective downdraft with an affected outflow area of less than 2½ miles wide and peak winds l asting less than 5 minutes. Microbursts may induce dangerous horizontal/vertical wind shears, which can adversely affect aircraft performance and cause property damage.

This image shows a further progression of the previous image with the microburst now spreading out as it impacts the ground. Winds can reach as high as 150 miles per hour with this type of feature.

A couple of pictures of microburst wind damage in the Wilmington NC area.

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National Weather Service
Weather Forecast Office, Wilmington NC
2015 Gardner Drive
Wilmington, NC 28405
(910) 762-4289

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Web Master's E-mail: ilm.webmaster@noaa.gov
Page Last Modified: November 23, 2008

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