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Tag: River Watch

Anticipating Break-up of Alaska’s Rivers: Pilot Observations Needed

As the long, cold and dark part of the year departs, break-up of Alaska’s rivers is getting underway.  The National Weather Service expects this that year, it could trend toward more of a mechanical event, with ice jams and flooding being more likely in some parts of the state.  NWS Hydrologist Crane Johnson presented the Alaska-Pacific River Forecast Center’s outlook at a webinar hosted by the Alaska Center for Climate Assessment and Policy (ACCAP).  Pilots are encouraged to consider participating in the River Watch Program this year,  sharing photos and/or pilot reports of ice conditions as we fly along the rivers between mid-April and perhaps into early June, to help monitor this situation.

Forecast for 2021
Factors that influence the nature of river break-up include thickness and areal extent of ice that formed over the winter, the quantity of the snowpack, and spring weather.   Crane was joined by ACCAP Climatologist Rick Thoman, who summarized the temperature and precipitation over the past winter and then looked ahead at the forecasts for the weeks ahead.  Based on this data, we should expect more of a mechanical break-up with the ice jams and associated flooding this year, as opposed to a gentle thermal break-up where ice largely melts in place and does not provide much resistance to the increased river flow associated with melting snows.  For more details on the processes in play, and the specifics of what areas are most at risk, I encourage you to watch the recording of the webinar, presented on April 13.

 

Breakups can vary in intensity depending on winter conditions, and how fast warming conditions develop in the spring. Based on existing conditions and forecasts, this season is expected to have more mechanical characteristics.

 Areas at Risk
Looking across the state, some regions are more at risk than others.  While ice thickness and snow cover are known to some extent, the remaining wild card is the temperature in the weeks ahead.  Based on forecast data to date, the break-up outlook map depicts an above average potential for flooding across the interior along the Yukon, Tanana and Kuskokwim drainages, as well as in the Copper River drainage and in the southeast panhandle.

The Spring Flood potential will be updated periodically. The current version will be found at: https://www.weather.gov/aprfc/floodpotential.

Historical Distribution of Ice Jams
While attention is often focused on the larger rivers, Crane also presented a map of the historic distribution of ice jams across the state.  It shows that they have occurred in more locations than just the major rivers.  Given this widespread distribution of possible locations for ice jams, observations from pilots can be particularly helpful to the River Forecast Center in monitoring break-up.

Ice jams can occur on a wide variety of rivers across the state. Consider flying segments of the smaller rivers to look for ice jams and related flooding.

What can Pilots Do?
If you are willing to devote some flight time to help the National Weather Service monitor break up this Spring, consider participating in the River Watch Program.  Initially designed to use Pilot Reports as the primary mechanism for reporting ice or flooding conditions, it now more commonly uses pictures taken with a smart phone (preferably with GPS turned on) of river conditions.  Email them to the River Forecast Office after getting back on the ground.

Information about the program, what to look for, and how to communicate results, is available on the River Watch page.  As the season progresses, NWS will update their breakup status map and indicate areas they are specifically interested in learning about–so check back periodically for updates.  Please keep in mind that not all communities are open to outside visitors; so, check the state’s Safe Travel site for local restrictions, before you plan your flights.

River Watch image on the Yukon River using the Theodolite App to capture location direction and altitude.

River Watch is a way for general aviation to contribute to the public good, while clearing out the cobwebs if you didn’t fly much over the winter.  Check out the details on the River Watch website and consider this a good reason to get airborne.  And while you are capturing river details with a smart phone, take time to file a Pilot Report or two with Flight Service when you are in locations that don’t have reported weather. Your PIREPs are appreciated!

Help NWS monitor river breakup, with PIREPs or pictures

Looking for a reason to go flying—even though it isn’t exactly summer yet?  Like to provide a public service at the same time?  With ice starting to melt in Alaska’s rivers, the National Weather Service (NWS) is once again happy to receive Pilot Reports and digital photos as they monitor breakup, and forecast possible flooding along our major rivers.  Pilots willing to supply observations are invited to participate in the River Watch Program.

2018 Breakup Forecast
To get a preview of breakup predictions this year, NWS has posted a five minute video with an overview of conditions going into the season.  Some parts of the state have an elevated flood potential, given snow pack, ice thickness and forecasts of the weeks ahead.  If you live in one of these areas, participating in River Watch could be very helpful, as the melt season progresses.

What is River Watch?
NWS established the River Watch Program to enlist the aid of pilots who are willing to provide information on the ice conditions as they fly. Pilots voluntarily participating in the program are provided basic information on the mechanisms of river ice break up, and asked to file Pilot Reports (PIREPs) while on routine flights.  FAA Flight Service specialists have also been trained to take these PIREPs, formatted with a special syntax.   NWS river hydrologists receive the PIREPs, providing them with a valuable set of observations in a timely fashion, describing ice or flooding conditions as the spring season progresses.

While the voluntary program initially targeted air taxi pilots, making their daily rounds, reports are welcomed from any pilot wishing to participate.  NWS has posted information their website that provides details about the program including the PIREP format to use, and terms to describe river ice conditions.

This document, available on the NWS website, describes the format for River Watch PIREPs, and common terms used to describe ice conditions at different stages of break-up

What’s new?
This program has been in place for many years, but technology is providing some new ways to interact.  While calling Flight Service with a PIREP is probably the fastest way to convey river conditions, here are some additional methods to provide information:

  • File a PIREP online. Last year, the Aviation Weather Center provided a portal that allows pilots to file PIREPs online.  It takes two steps: first establish an account with the AWC (it’s free), and then request the ability to file PIREPs.  After that one-time approval you will now have access to the PIREP submission form under the Tools menu, while signed into your account.  (See link below for details). Study the details on River Watch PIREP formats in the reference links below.
  • Send an e-mail, directly to the river forecasters. If you have a more detailed report than fits in a PIREP, providing the information in an email after you land may be a better way to go.  To help with geographic reference, NWS has marked up flight charts segments with river miles along major river basins. You may print one of these for the intended route, making it easier to communicate locations of ice jams, or other features.  It may also be worth printing the River Ice PIREP format, with standard terms to describe ice and flooding conditions.
  • Send pictures directly to NWS forecasters—with the locations imbedded in them. If using an iPhone

    A photo taken using the Theodolite App on an iPhone. GPS coordinates are displayed on the image, with the viewing direction and other data. More importantly, the coordinates are also included in the EXIF file associated with the image. This allows NWS to import the image directly into their system, showing the location where the image was taken. Other apps also capture GPS locations, if permissions are set to enable that feature.

    or other camera that has the ability to attach GPS coordinates, (typically in the form of an EXIF format file), NWS may be able to import the photo location directly, to see where each picture was taken. In some cases, a picture is worth a thousand words!

  • Phone calls are yet another way to report river conditions. Call the River Forecast Center directly at 1-800-847-1739 during the hours between 6 am and 5 pm, especially if you observe a flood developing, or other hazardous condition.

Regardless of how you choose to provide information, consider using the increasing hours of daylight, and the need to monitor river conditions as an excuse to peel off the wing covers and take to the skies.  It is a good excuse to go flying. It also helps the river forecasters and the residents who live along the rivers, who need to know what to expect as the ice goes out this spring!

 

Reference Links:
River Watch Program overview: https://www.weather.gov/aprfc/riverwatchprogram

Filing PIREPs online: https://www.aopa.org/news-and-media/all-news/2017/may/16/nws-website-accepts-distributes-pilot-reports

River Watch Poster: https://www.weather.gov/media/aprfc/rwpflyer.pdf