Frequent Questions

1. Where did Capital Weather Gang come from?
2. Who's on the team?
3. You all use the word "team" a lot? Why is that so important?
4. Can't I get my weather forecast from the local TV news, the Weather Channel, the radio, or from Web sites like weather.com and AccuWeather.com? What makes Capital Weather Gang different?
5. Do you make your own forecasts, or are you just repeating what the National Weather Service says?
6. What's wrong with the National Weather Service forecast?
7. How should I interpret forecast confidence?
8. When does the Snow Lover's Crystal Ball appear?
9. What do the StormCast snowflakes, SchoolCast apples, TravelCast airplanes, and FedCast Capitol Domes mean?
10. What is the Storm Threat Level?
11. What does the Nice Day Sun mean?
12. What's the difference between partly sunny and partly cloudy?
13. What does a 40% chance of rain really mean?
14. Does Capital Weather Gang post on climate change and other politically charged issues? Is Capital Weather Gang a partisan blog?
15. What's the difference between a watch, warning and advisory?
16. Where can I get past weather data for the D.C. area?

Where did Capital Weather Gang come from?

In 2002, with a passion for weather and a master's degree in meteorology under his belt, Jason Samenow developed the idea of a weather Web site focused on the DC area. Launched in 2003, CapitalWeather.com was a set of useful weather links and occasional forecast commentary before, during and after significant weather events. The site quickly attracted a small following of family, friends and weather enthusiasts.

At the same time, blogs were springing up all over the Internet. Blogs (short for weblogs) have taken on various forms and purposes, but at their core they have served as a way to communicate information in a timely manner while providing a mechanism for users to interact with each other and the author. The blog concept fit perfectly with Jason's vision to create a site where visitors could learn about changing weather conditions and interact with weather experts. With the help of Jamie Jones, an eager computer science major at Jason's alma mater, the University of Virginia, CapitalWeather.com became what is believed to be the world's first local weather blog in February 2004.

Since then, Jason has assembled a talented and diverse team of forecasters and photographers, most of whom have degrees in meteorology. In January 2008, CapitalWeather.com moved to washingtonpost.com and became the Capital Weather Gang blog. The blog targets both the general public and weather enthusiasts, providing the most insightful and entertaining weather information available for the metropolitan D.C. area, including news, analysis, local forecasts, features, photographs and data. It also offers lots of interactive opportunities for readers.

Who's on the team?

There are 10 of us -- six forecasters, one columnist, two photographers and one information technology specialist. We all have a passion for the weather and for effectively communicating weather information to the general public and weather enthusiasts. Learn more about the team on our Meet the Gang page.

You all use the word "team" a lot? Why is that so important?

Capital Weather Gang forecasters work as a team to provide the most accurate weather forecast possible. During routine weather, each forecaster tries to build on the previous forecaster's prediction, with the goal of honing in closer and closer to the correct forecast. Leading up to and during significant weather events, such as winter storms, Capital Weather Gang forecasters carefully review and discuss all of the data available before presenting a "Team Forecast." We believe a consensus forecast is often more accurate than that by any one individual.

Can't I get my weather forecast from the local TV news, the Weather Channel, the radio, or from Web sites like weather.com and AccuWeather.com? What makes Capital Weather Gang different?

Capital Weather Gang vs. TV and radio:

To get the weather on TV or radio, you have to do so on that station's schedule. At Capital Weather Gang, accurate and detailed weather information for the DC area is always at your fingertips, and is updated whenever changing models and weather conditions warrant. Also, TV and radio stations don't typically offer the kind of access to their forecast team that Capital Weather Gang does. We encourage visitors to comment or ask questions, and those who do usually receive an expert response in a timely manner.

Capital Weather Gang vs. Other Internet Sites:

Unlike the computer-generated forecasts found at most traditional weather Web sites, our forecasts are prepared by human beings who know the Washington area and have experience forecasting here. Thanks to our local knowledge and experience, and the flexibility of our format, we're able to offer more forecast details than other Web sites. We try to paint a picture of the day and describe how the weather will affect your life -- whether you're going to the supermarket, a festival on the Mall or a Nationals game. In addition, different levels of detail allow those who wish to dig deeper into our content to find out why the weather is doing what it's doing.

Do you make your own forecasts, or are you just repeating what the National Weather Service says?

Yes, we absolutely make our own forecasts (that meteorology training would've been quite a waste if we didn't). As is the case of any weather forecasting outlet, most of the raw data we use to construct the forecast comes from the National Weather Service, which operates several computer weather models. But it's up to us to interpret the data and leverage our local experience to come up with as accurate and detailed of a forecast as possible.

What's wrong with the National Weather Service forecast?

Nothing at all. We think the National Weather Service does a fantastic job, and is an invaluable asset to the nation's society and economy. But the forecast it provides for public consumption is limited in nature, in part due to its specific mission as a government agency. At Capital Weather Gang, we strive to include as many forecast details as possible, though still presented in a concise fashion. For example, when model data is conclusive enough, we'll pinpoint the most likely timing of rain or snow (e.g., not until after the morning commute, or between 4 and 9 p.m.). Also, we focus on communicating the uncertainty associated with a given forecast, and whether there is more than one possible scenario.

How should I interpret forecast confidence?

Not every forecast is a sure bet. Sometimes the various computer models that we look at when making a forecast are in complete agreement, allowing us to predict with high confidence. Sometimes they differ widely from each other, in which case our confidence may be low. Still other times, guidance from the models combined with our experience and even gut instinct warrant a confidence somewhere in-between. Rather than pretend we know exactly what's going to happen when we really don't, the forecast confidence indicators are an easy way for us to communicate the uncertainty of a forecast.

Generally speaking, here's how you should interpret the different levels:

• High: Bank on it.
• Medium-High: Overall forecast is sound, but minor variations are possible.
• Medium: We think we're on the right track, but the forecast details are still taking shape.
• Low-Medium: This is our best guess, but don't hold us to it.
• Low: Crapshoot.

What do the StormCast snowflakes, SchoolCast apples and TravelCast airplanes mean?

The following impact forecasts are issued leading up to and during winter storms:

StormCast

Nuisance Event: Little or no snow/ice accumulation. Roads not hazardous.
Minor Event: Some accumulation (Dusting to 2 inches). Untreated roads hazardous. Slick spots possible on treated roads during heavy precipitation.
Major Event: Significant snow/ice accumulations (3-7 inches). Widespread hazardous road conditions.
Extreme Event: Crippling snow/ice accumulations (8 inches or more). Travel discouraged.

TravelCast

Airports expected to operate with little or no delay due to weather
Minor airport delays expected
Major airport delays expected
Airport closures expected

SchoolCast

Do your homework. You're probably having school.
50/50 chance for school. Good chance of at least a delay or early dismissal. Do your homework now, so you don't have to sweat it later.
It's probably safe to blow off the homework, but your day off will be more enjoyable if you do it now.
Most or all area schools are officially closed.

FedCast

Expect to report to work on time
50/50 chance of unscheduled leave policy, delay, or early closing
Greater than 90% chance of unscheduled leave policy, delay, or early closing. 50% or less chance of shutdown.
Greater than 75% chance of shutdown. Near certainty of unscheduled leave policy.

What is the Storm Threat Level?

Our new Storm Threat Level graphic is aimed at promoting storm preparedness on days when thunderstorms are possible. The three levels are:

When does the Snow Lover's Crystal Ball appear?

The Snow Lover's Crystal Ball appears when the potential exists for accumulating snow beyond 24 to 36 hours. It includes the predicted timing, probability and potential impact of the snow, as well as commentary that examines the various scenarios that might occur.

What does the Nice Day Sun mean?

The Nice Day Sun is awarded for days that are expected to meet the following criteria:

• At least 50% sunshine
• Probability of rain less than 20%
• High temperatures from 65-85
• Dewpoints no higher than 65
• Wind gusts generally less than 25 mph

A confidence of at least "Medium-High" is required for those days awarded the Nice Day Sun. Thus, it is rarely given for forecasts beyond 48 hours.

What's the difference between partly sunny and partly cloudy?

Different forecasters and forecast outlets have different answers to this question. Here's what we think makes the most sense: They both mean the same thing -- a mix of sun and clouds. We tend to use partly sunny for daytime forecasts and, obviously, partly cloudy for nighttime. Sometimes we'll use partly cloudy during the day to highlight a change from sunnier to cloudier skies.

What does a 40% chance of rain really mean?

Simply put, it means that any location in the forecast area has a 40% chance of receiving measurable rain during the forecast period. In other words, statistically, for every 10 times we forecast a 40% chance of rain where you live, you should receive measurable rain four times.

Does Capital Weather Gang post on climate change and other politically charged issues? Is Capital Weather Gang a partisan blog?

The weather, and how it affects the daily lives of those living in and visiting the DC area, will always be our main focus. But we would be remiss to not comment from time to time on climate change and other politically charged issues related to the environment (this is Washington, after all). Capital Weather Gang is officially non-partisan. However, its writers may offer opinions on policies adopted or championed by a particular public figure or political party. These opinions are those held expressly by the writer and do not represent an official position of Capital Weather Gang.

What's the difference between a watch, warning and advisory?

The National Weather Service issues watches, warnings and advisories, which we report here at Capital Weather Gang, for significant and hazardous weather including winter storms, severe thunderstorms, tornadoes, flash floods and excessive heat.

A watch means that the potential exists for significant and hazardous weather, while a warning means that significant and hazardous weather is imminent or already occurring. An advisory indicates that inclement weather is expected to cause a significant inconvenience, but not serious enough to warrant a warning.

The criteria required to issue a watch, warning or advisory is different for different parts of the country. Definitions for the D.C. metro area can be found here.

Where can I get past weather data for the D.C. area?

Past weather data for the D.C. area is available at the National Weather Service Baltimore/Washington Web site. Also, at Weather Underground, past weather data can be obtained for the nearest reporting station through zip code, airport or city queries -- enter your location of interest at the top of the page and scroll down to "History and Almanac." Weather data for official purposes can be obtained from the National Climatic Data Center.