National Weather Service United States Department of Commerce

Heavy Rainfall and Flooding Concerns in the Southwest; Coastal Low to Impact the East Coast

Deep tropical moisture will lead to widespread showers and thunderstorms capable of producing flash flooding through early next week over the Southwest and Four Corners. A coastal storm is expected to develop off the southeast U.S. coast tonight and is expected to strengthen and bring flooding, dangerous rip currents, gusty winds and heavy rain up much of the East Coast through early next week. Read More >

Anytime a tropical cyclone (TC) is in the WFO Guam Area of Responsibility, WFO Guam issues increasing
information regarding the TC(s). At a minimum, Public Advisories are issued every 6 hours, but as TC
watches/warnings are issued for islands (lead times of 48hr/24hr of the arrival of damaging winds (39 mph / 34
kt)), Public Advisories increase to every 3 hours, as well as the 6-hourly issuance of the Local Statements. More
information about our special TC text products is below, as well as a 12-hour clock cycle of our TC operational
schedule.

 

Public Advisory (TCPPQ#)

  • A plain-language interpretation of the JTWC warning bulletin.
  • Provides latest information on tropical storm/typhoon watches and warnings.
  • Issued at least every 6 hours when a tropical cyclone is expected to affect WFO Guam's Area of Responsibility.
  • Issued every 3 hours when TC watches or warnings are in effect for any of WFO Guam’s 39 TC
    warning points.

Local Statement (HLSPQ#)

  • Specific forecast for each island under a watch or warning, including rain, wind, surf, storm surge and coastal inundation, as well as recommended preparations.

Tropical Cyclone Update (TCUPQ#)

  • Hourly radar-based position estimates of a TC when within the range (about 230 miles) of Guam's Doppler radar.
  • Issued hourly near the top of the hour when a center position fix is available.
  • May also be issued, at any time, for significant changes, notable observations, or notable events
    occurring in the development or progress of a TC in the Marianas.

Post-Storm Tropical Cyclone Reports (PSHGUM)

  • Brief history of a TC requiring WFO Guam’s issuance of TC watches/warnings.
  • Observational data from islands or surrounding marine zones during the TC passage.
  • Impacts narratives from each island affected by a passing TC.

 

 

A graphical representation of a analog clock to show when certain Tropical Cyclones products are issued. JTWC Forecasts are updated around 1 and 7 AM/PM. TCPs are issued  at 2 AM/PM and 8 AM/PM. HLS's are issued at 3 AM/PM and 9 AM/PM, with TCP (Intermediate) issued at 5 AM/PM and 11 AM/PM.