August 2025 EZNews

Hello and thank you for taking a few minutes to read the 52nd edition of EZNews!

We appreciate those members who have opted for automatic monthly renewal of their EZWxBrief membership. If you haven't yet set up your account to renew automatically, please sign in and follow the prompts if your membership has expired. Otherwise, go to the User Profile page (see right) and tap or click on the Renew button. This allows you to set up your monthly renewal using a Visa, MasterCard, or Discover credit card (we do not accept American Express at this time), ensuring you continue to enjoy the simplicity of EZWxBrief.

Are you new to EZWxBrief?

For members new to EZWxBrief, you won't find EZWxBrief in the App Store or Google Play Store. For the best user experience, EZWxBrief is optimized to run as a progressive web app (PWA) and must be installed on your device. This is quick and painless and takes less than 10 seconds per device. Follow the instructions in this video or visit the 180+ page Pilots Guide for more information on how to install EZWxBrief as a PWA on all of your devices. For example, shown to the left, here's how to install EZWxBrief on your iPhone or iPad...it's that EZ!

In Flight Weather Essentials for Pilots eight-week class now open for registration

There's no doubt that fair weather environments and severe clear conditions provide the best flying experience. However, pilots that use their aircraft to travel longer distances and those that fly more frequently will inevitably increase their exposure to some adverse weather. This class will enable you to recognize serious adverse weather environments both in how to avoid them and provide guidance on how to negotiate the best path out of them or around them. In the end, this class isn't about dealing with weather emergencies as they occur, but how to avoid them before they happen.

In a nutshell, this eight-week course is specifically directed at certificated private/commercial pilots, flight instructors and designated pilot examiners who feel their weather skillset is significantly lacking. It is open to pilots with and without an instrument rating. Putting it succinctly, this is designed to take the serious cross country pilot to the next level.

The live class, In Flight Weather Essentials for Pilots will begin on Monday, September 15, 2025. The class will meet each subsequent Monday night for eight total weeks. This announcement is a little bittersweet given it will be the last live class that Scott teaches as he eases into retirement over the next few years. So, if you are interested in enduring one more class with Scott, registration has begun so you can reserve your spot as there are only a few seats remaining for this class. Tuition is $345.

Register now >>> 

Once your registration is complete, you should receive two emails. The first is a confirmation of the payment for your registration and a second is the Google Meet link to join each session. Please check your spam folder if they have not reached your inbox. Important: the same link will be used for each and every class.

Each class will start promptly at 8 pm eastern time on Mondays beginning on September 15, 2025. You can expect about 45-60 minutes of instruction with 15 minute s added to allow for questions and spillover. The sessions will be held using Google Meet and each class will be recorded and a personal link to the recording along with a PDF of the presentation and quiz will be provided to you within 36 hours. Therefore, it is not mandatory that you attend each live class to get the most from the eight-week course. Although you can join the class on a handheld device using the Google Meet app, it is recommended that you use a laptop or desktop computer (Google Chrome is recommended).

While it is not mandatory that you previously attended the Weather Essentials and Advanced Weather Essentials for Pilots classes, it is highly recommended. You can purchase a recording of these two classes here and here, respectively. Save even more by purchasing our limited-time combo deal here.

AirVenture 2025 was a huge success!

This is a little bittersweet since this will be the last time we will attend AirVenture as a vendor. Nevertheless, it was great to meet many of you again this year either at the EZWxBrief booth in Hangar C or at one of Scott's seven presentations. Scott had the chance to demo version two of the EZWxBrief progressive web app to over 120 attendees throughout the week. It was great to hear the positive feedback and the many suggestions.

Overall, the weather at the show started out pleasant but was warm and humid throughout the week. There were a few rain showers and a thunderstorm that rolled through the Oshkosh area Wednesday evening producing an outflow with strong, gusty winds. This did not significantly affect the event that once again had a record-setting attendance of 704,000 people.

Airline delays due to weather

Ever wonder about weather delays when you are flying on a commercial flight and there doesn't appear to be an obvious reason for this delay? This may be due to the lightning warning system at the airport. Many of the major airports have a lightning detection system installed. This isn't primarily for pilots, but more for the safety of ground personnel working on the ramp when thunderstorms are nearby. When early warning and detection systems identify cloud-to-ground lightning occurrence in the vicinity of an airport, a series of personnel safety procedures is triggered to protect airline ramp operators or technicians of highly exposed areas such as aircraft parking aprons and tower buildings from lightning strike risk.

Electric Field Mill (EFM) from Boltek

There are many different systems installed at these high-impact airports that range in capability. For some airports such as Dallas Fort Worth International Airport (KDFW), there are no airport-owned or provided equipment. Users rely on self-installed equipment. Charlotte Douglas International Airport (KCLT) has an airport-owned system made by Vaisala. The Vaisala Precision Lightning Weather System (PLWS), is a predecessor of the TWX1200 (Vaisala Thunderstorm Warning System 1200) with a feed from the National Lightning Detection Network (NLDN) and two electric field mills (EFM). Electric field mill (EFM) sensors like the one show above are used to detect the potential for lightning by measuring the atmospheric electric field so they don't directly detect lightning strikes but rather the buildup of electrical charge in the atmosphere that precedes lightning.

The light signals like the one shown below are intended to convey current conditions for thunderstorms and potential for lightning strikes.

• Green indicates EFMs do not exceed alarm thresholds and no lightning within 12 miles, or no EFM alarm and no lightning in past 5 minutes.

• Green/yellow indicates one EFM at alarm threshold, or lightning strike within 12 miles.

• Yellow indicates two EFMs at alarm threshold, or lightning strike within 12 miles and one EFM at alarm threshold, or lightning strike within 6 miles.

• Yellow/red indicates two EFMs at alarm threshold and a lightning strike within 12 miles, or lightning strike within 8 miles and one EFM at alarm threshold.

• Red indicates lightning strike within 3 miles, or a lightning strike within 8 mis and two EFMs at alarm threshold.

  
  

Light signals located around the ramp areas at the Charlotte Douglas International Airport

Below is the lightning activity at the ten busiest U.S. airports over the past 10 years. Not surprising that most of the high-impact airports are in the Southeast U.S.

Can wind farms cause lightning?

You have probably been taught that you should never seek shelter under a tree when thunderstorms are nearby. But you will never want to seek shelter under a wind turbine either!

Indeed, it is accurate that wind farms attract lightning and can also induce it. Wind turbines are large structures situated in relatively flat areas, making them prone to lightning activity. Their size and design can trigger lightning strikes as well. This phenomenon occurs when a turbine generates upward lightning in response to a nearby natural lightning flash. Additionally, a turbine can initiate a lightning strike even in the absence of a nearby thunderstorm. This can happen when electrification in the lower atmosphere causes lightning to originate from the turbine, particularly during colder months. A study was done that analyzes nine years of data to pinpoint the U.S. wind farms most susceptible to lightning. Topping the list is a wind farm in Pushmataha County, Oklahoma, which experiences an average of 10 lightning strikes per turbine each year. One turbine at this location has been struck 111 times since 2019.

Retirement of the NAM, HREF and HRW forecasts

The NWS is retiring several models during the first or second quarter next year (2026). This includes the North American Mesoscale (NAM), High Resolution Ensemble Forecast (HREF), Short Range Ensemble Forecast (SREF) and the High Resolution Window (HRW) models. The new Rapid Refresh Forecast System (RRFS) is now undergoing development and is expected to go operational early next year.

This new forecast model will have a resolution of 3 km. But the most important improvement will be the vertical resolution. It will use 65 layers similar to the GFS model as compared to the High Resolution Rapid Refresh that only has 50 layers in the vertical. More vertical layers will provide better forecasts for mixed precipitation of snow, sleet, freezing rain and rain. This is a key component of a winter storm forecast. More vertical layers will also help with warm-season severe thunderstorm forecasting.

The RRFS will cover all of North America, which is a larger coverage area than the current HRRR. The RRFS will run every hour and most of the runs will provide an 18 hour lead time. A run every six hours will provide a 60 hour lead time.

Improvements to MRMS begin August 5, 2025

What is MRMS you ask? Well, take a look at this post. If you fly with the Flight Information System-Broadcast (FIS-B) datalink weather, this improvement should create a much higher quality picture. The MRMS quality control routines will be updated to improve handling of excessive ground clutter and beam blockage at certain radar sites. New wind farm location tables will also be implemented in this release. Wind farms tend to produce a fair amount of ground clutter which can appear on radar similar to what you might see in a thunderstorm.

Discontinuation of TAF sites

The NWS is discontinuing the issuance of TAFs for the following airports:

• Talladega Municipal Airport in Talladega, AL (KASN) effective October 15, 2025.

• Las Vegas Municipal Airport near Las Vegas, NM (KLVS) on or before November 1, 2025

• Tucumcari Municipal Airport near Tucumcari, NM (KTCC) on or before November 1, 2025

•  Bryce Canyon Airport in Bryce, UT (KBCE) effective September 16, 2025.

EZWxBrief v2 News

NOAA/NWS will be retiring the Model Analysis and Guidance (MAG) website later this year. This site has been used by the EZWxBrief progressive web app to download and render a subset of the static imagery collections that include the GFS, NAM, HRRR, HREF and HRW-FV3 models. The retirement of the MAG site is part of an overall effort to privatize NOAA and remove resources such as these from the public view.

Consequently, in order to provide a similar version of these charts to EZWxBrief subscribers, the forecasts for the GFS, HRRR and HREF models have been built from scratch using NOAA's highly compressed raw forecast model data. A sample of the new 500 mb GFS constant pressure chart is shown above.

NOAA expects a majority of this raw model guidance to be available for the time being, although there is an expectation that it will also eventually be discontinued. Please note, this has not been a trivial development task and requires significant computing resources to build all of these charts. As a result, the fee charged for the EZWxBrief app will increase by $1.00 beginning on December 1, 2025 to cover a portion of this initial development and ongoing compute cost. We hope you understand the need for this change and continue to value the simplicity of EZWxBrief.

EZWxBrief v2.0.3 is the current version. There have been no new releases at this point in time. A majority of the work over the last six months has been to optimize the compute architecture to improve the app's overall performance and security from any further attacks.

Most pilots are weatherwise, but some are otherwise™

Dr. Scott Dennstaedt

Weather Systems Engineer

Founder, EZWxBrief™

CFI & former NWS meteorologist