CIMSS

08/17/2026

Why is wildfire smoke unhealthy? Ask the Weather Guys!

The smoke from wildfires can linger in the air and often travels long distances carrying unhealthy matter.Depending on how hot the fire is and what’s burning — trees, grasslands, or buildings — wildfire smoke can contain toxic chemical substances, including carbon monoxide, carbon dioxide, sul...

08/15/2026

No hurricane on record has hit the Big Island of Hawaii. Below is all historical tracks from 1842 to 2025. Hurricane Lala would be the first. This is hard to do as the mountainous terrain has a tendency to deflect storms. We will see if it actually goes "feet dry". It is going to be very close. There will be incredible and dangerous rainfall and flooding on the windward facing slopes. Perhaps over 20 inches. The region is still wet from heavy rains earlier this year. The mountain areas and valleys will also experience hurricane force wind gusts.

08/10/2026

Has 2026 been an active year for tornadoes? Ask the Weather Guys!

A tornado is a violently rotating column of air that is in contact with both the surface of Earth and the storm above. The 30-year normal (1981-2010) for Wisconsin is 23 tornadoes per year.As of mid-July, the National Weather Service has confirmed that our state has experienced 39 documented tornado...

08/03/2026

What causes the phenomena of atmospheric ducting? Ask the Weather Guys!

Atmospheric ducting is a phenomenon that affects how radio waves travel through our atmosphere.Radio waves are a type of electromagnetic energy that carry information as they travel by modifying certain properties of the wave, like their amplitude or frequency. In a vacuum, radio waves travel at the...

07/31/2026

Today at the CIMSS online Weather Camp we had two broadcast meteorologists join us. Dr. Matt Sitkowski from The Weather Channel and Emma Hietpas from WKOW here in Madison. The students learned about the varied career paths of both of our speakers along with the joys and challenges of presenting weather information live on-air.

07/28/2026

There has been a lot of effort recently to better understand the dynamics associated with vortex alignment in hurricanes and it's role in rapid intensification. Alex DesRosiers from the National Academy of Sciences dropped by our online CIMSS Weather Camp just yesterday to share some of his research on this very topic with our 55 high school students. All this weak CIMSS is conducting this online Weather Camp to give students an opportunity to learn about the science of hurricanes, tornadoes, winter storms and other weather topics. Each day features a guest speaker from a sub-specialty in meteorology.

A new NOAA-led study drawing on nearly three decades of Hurricane Hunter airborne radar data has pinpointed four storm characteristics that signal when a tropical cyclone is likely to achieve vertical alignment and undergo rapid intensification, offering forecasters earlier warning tools.

07/28/2026

Here is a nice example of value added by commercial weather satellites along with the collaboration with NOAA through the Commercial Data Program (CDP). Typhoon Dolphin is currently undergoing rapid intensification on it's way to a likely powerful super typhoon. There have been no recent microwave passes since the 0743Z SSMIS F-16 pass which did show a developing eyewall and good banding. CIMSS gets the data from NOAA through the CDP to provide value added tropical cyclone products. Two Tomorrow.io TMS passes came in at 1103Z (TMS09) and 1116Z (TMS06) that provided estimates of 105 knots, 20 knots higher than the 80 knot best track intensity (dashed line below) at the time from JTWC. These support the ongoing rapid intensification from 60 to 100 knots in 12 hours. JTWC is now at 100 knots in agreement with these estimates putting that estimate well above the subjective Dvorak estimates which ranged from 77-90 knots. This also underscore the idea that tropical cyclone analysis is a multi-spectral problem requiring multiple types of satellites and sensors/frequencies. A single satellite image rarely tells the full story.

07/20/2026

How can you tell whether the air is comfortable? What does wet bulb temperature mean? Ask the Weather Guys!

The wet-bulb temperature is the lowest temperature to which unsaturated air can be cooled by evaporating liquid water into it.This may sound horribly obscure, but it serves as a very useful measure of human comfort. It combines atmospheric humidity and temperature in a way that helps determine our c...

07/13/2026

Can we get forecasts for fires? Ask the Weather Guys!

Wildfire outbreaks require the alignment of several factors, including temperature, humidity, winds and the lack of moisture in fuels such as trees, shrubs and grasses. These factors have strong direct or indirect ties to current weather, climate variability and climate change. The National Oceanic....

07/09/2026

What's a "wake low"? Ask the Weather Guys!

Wake lows are short-lived mesoscale phenomena. Mesoscale weather ranges from about 5 kilometers to 1,000 kilometers in size.Wake lows are relatively uncommon. They produce strong winds after a storm moves out. The term