NWS Forecast Office Codes

What is the NWS? #

The National Weather Service (NWS) is the U.S. agency responsible for weather forecasts, warnings, and observations. Organized into 122 local Weather Forecast Offices (WFOs) plus national centers like SPC, NHC, and WPC.

What is a WFO? #

A Weather Forecast Office (WFO) is a local NWS office responsible for issuing warnings and forecasts for a specific County Warning Area (CWA). There are 122 WFOs across the U.S.

What is ABQ? #

ABQ is the NWS Weather Forecast Office for Albuquerque, New Mexico. Covers central and western New Mexico.

What is ABR? #

ABR is the NWS Weather Forecast Office for Aberdeen, South Dakota. Covers north-central South Dakota.

What is ACE? #

ACE (Accumulated Cyclone Energy) is the standard metric for total tropical cyclone seasonal activity. It sums the square of maximum sustained winds every 6 hours for all systems at tropical storm intensity or greater. High ACE = very active and/or intense season. An average Atlantic season produces around 100 ACE units; hyperactive seasons like 2020 and 2005 produced 180–250+.

What is AFC? #

AFC is the NWS Alaska Forecast Center in Anchorage, Alaska. Provides statewide forecasts and climate services for Alaska.

What is AFG? #

AFG is the NWS Weather Forecast Office for Fairbanks, Alaska. Covers interior Alaska, the Brooks Range, and the North Slope.

What is AJK? #

AJK is the NWS Weather Forecast Office for Juneau, Alaska. Covers southeast Alaska, the Alaska Panhandle, and the Inside Passage.

What is AKQ? #

AKQ is the NWS Weather Forecast Office for Wakefield, Virginia. Covers southeast Virginia, northeast North Carolina, and the Hampton Roads area.

What is ALY? #

ALY is the NWS Weather Forecast Office for Albany, New York. Covers eastern New York and western New England.

What is AMA? #

AMA is the NWS Weather Forecast Office for Amarillo, Texas. Covers the Texas Panhandle and eastern New Mexico.

What is ANC? #

ANC is the NWS Weather Forecast Office for Anchorage, Alaska. Covers south-central Alaska including the Matanuska-Susitna Valley.

What is APX? #

APX is the NWS Weather Forecast Office for Gaylord, Michigan. Covers northern lower Michigan and lake-effect snow from Lakes Michigan and Huron.

What is ARX? #

ARX is the NWS Weather Forecast Office for La Crosse, Wisconsin. Covers western Wisconsin, southeastern Minnesota, and northeastern Iowa.

What is ASW? #

ASW is the EAS/SAME code for an Air Stagnation Warning. It is issued when a persistent, stagnant air mass traps pollutants near the surface, allowing air quality to deteriorate over time. Common setup: light winds, poor vertical mixing, and a temperature inversion.

What is AVA? #

AVA is the EAS/SAME code for an Avalanche Watch. It means conditions are becoming favorable for avalanches in steep terrain, but the threat is not yet as immediate as an Avalanche Warning.

What is AVW? #

AVW is the EAS/SAME code for an Avalanche Warning. It means dangerous avalanche conditions are occurring or expected soon. Avoid avalanche terrain and follow local avalanche center guidance.

What is BGM? #

BGM is the NWS Weather Forecast Office for Binghamton, New York. Covers the Southern Tier and Finger Lakes of New York.

What is BIS? #

BIS is the NWS Weather Forecast Office for Bismarck, North Dakota. Covers western and central North Dakota.

What is BMX? #

BMX is the NWS Weather Forecast Office for Birmingham, Alabama. Covers central and northern Alabama.

What is BOI? #

BOI is the NWS Weather Forecast Office for Boise, Idaho. Covers southwestern Idaho and eastern Oregon.

What is BOU? #

BOU is the NWS Weather Forecast Office for Denver/Boulder, Colorado. Covers the Denver metro area and the Colorado Front Range.

What is BOX? #

BOX is the NWS Weather Forecast Office for Boston, Massachusetts. Covers eastern New England including Cape Cod.

What is BRN? #

Bulk Richardson Number (BRN) is the ratio of CAPE to vertical wind shear. Values of 10–45 favor supercells, >50 favor multicells or weakly organized storms.

What is BRO? #

BRO is the NWS Weather Forecast Office for Brownsville, Texas. Covers the Lower Rio Grande Valley and the Gulf Coast near the Mexico border.

What is BTV? #

BTV is the NWS Weather Forecast Office for Burlington, Vermont. Covers Vermont and the Lake Champlain Valley.

What is BUF? #

BUF is the NWS Weather Forecast Office for Buffalo, New York. Covers western New York, known for intense lake-effect snow off Lake Erie and Lake Ontario.

What is BYZ? #

BYZ is the NWS Weather Forecast Office for Billings, Montana. Covers south-central Montana and northern Wyoming.

What is BZW? #

BZW is the EAS/SAME code for a Blizzard Warning. Triggers on NOAA Weather Radio for your county when a Blizzard Warning is in effect. See the full Blizzard Warning definition for criteria.

What is CAE? #

CAE is the NWS Weather Forecast Office for Columbia, South Carolina. Covers central South Carolina.

What is CAR? #

CAR is the NWS Weather Forecast Office for Caribou, Maine. Covers northern and eastern Maine.

What is CFA? #

CFA is the EAS/SAME code for a Coastal Flood Watch. It means coastal flooding is possible, usually from tide, surge, large waves, or water piling up along the shoreline.

What is CFW? #

CFW is the EAS/SAME code for a Coastal Flood Warning. It means coastal flooding is expected or occurring and can make normally dry shoreline roads, lots, and low-lying areas unsafe.

What is CHS? #

CHS is the NWS Weather Forecast Office for Charleston, South Carolina. Covers the South Carolina coast and Lowcountry.

What is CIN? #

CIN (Convective Inhibition) is the energy needed to overcome a stable layer before a parcel can rise freely. Strong CIN suppresses storms; just enough CIN can delay initiation until storms can become discrete supercells.

What is CLE? #

CLE is the NWS Weather Forecast Office for Cleveland, Ohio. Covers northern Ohio and is responsible for lake-effect snow from Lake Erie.

What is CRP? #

CRP is the NWS Weather Forecast Office for Corpus Christi, Texas. Covers the Texas Coastal Bend.

What is CTP? #

CTP is the NWS Weather Forecast Office for State College, Pennsylvania. Covers central Pennsylvania and the Susquehanna Valley.

What is CYS? #

CYS is the NWS Weather Forecast Office for Cheyenne, Wyoming. Covers southeastern Wyoming and the Nebraska Panhandle.

What is DDC? #

DDC is the NWS Weather Forecast Office for Dodge City, Kansas. Covers southwest Kansas — classic tornado alley territory.

What is DLH? #

DLH is the NWS Weather Forecast Office for Duluth, Minnesota. Covers northeastern Minnesota and the western Lake Superior shoreline.

What is DMX? #

DMX is the NWS Weather Forecast Office for Des Moines, Iowa. Covers central Iowa.

What is DSW? #

DSW is the EAS/SAME code for a Dust Storm Warning. It is issued for blowing dust that creates life-threatening travel conditions, often with near-zero visibility. Pull off the road, turn lights off, and keep your foot off the brake.

What is DTX? #

DTX is the NWS Weather Forecast Office for Detroit, Michigan. Covers southeast Michigan and lake-effect snow from Lake Huron.

What is DVN? #

DVN is the NWS Weather Forecast Office for Quad Cities, Iowa (Davenport). Covers eastern Iowa and northwestern Illinois.

What is EAX? #

EAX is the NWS Weather Forecast Office for Kansas City/Pleasant Hill, Missouri. Covers western Missouri and eastern Kansas, including the Kansas City metro.

What is EHI? #

Energy Helicity Index (EHI) combines CAPE and SRH. EHI > 1 favors supercells with tornado potential; >5 is associated with violent tornadoes.

What is EHW? #

EHW is the EAS/SAME code for an Excessive Heat Warning. It means dangerously hot conditions are expected or occurring, with a high risk of heat illness for people without cooling, hydration, or breaks from the heat.

What is EKA? #

EKA is the NWS Weather Forecast Office for Eureka, California. Covers the Northern California coast and the Klamath Mountains.

What is EPZ? #

EPZ is the NWS Weather Forecast Office for El Paso, Texas. Covers far west Texas, southern New Mexico, and the Juarez metro area.

What is EWX? #

EWX is the NWS Weather Forecast Office for Austin/San Antonio, Texas. Covers south-central Texas.

What is EYW? #

EYW is the NWS Weather Forecast Office for Key West, Florida. Covers the Florida Keys and extreme southern Florida waters.

What is FFC? #

FFC is the NWS Weather Forecast Office for Atlanta, Georgia. Covers northern and central Georgia.

What is FGF? #

FGF is the NWS Weather Forecast Office for Grand Forks, North Dakota. Covers eastern North Dakota and the Red River Valley.

What is FGZ? #

FGZ is the NWS Weather Forecast Office for Flagstaff, Arizona. Covers northern Arizona including the Colorado Plateau and Grand Canyon area.

What is FSD? #

FSD is the NWS Weather Forecast Office for Sioux Falls, South Dakota. Covers eastern South Dakota and southwest Minnesota.

What is FWD? #

FWD is the NWS Weather Forecast Office for Dallas/Fort Worth, Texas. Covers north-central Texas, one of the most active severe weather regions in the U.S.

What is FZW? #

FZW is the EAS/SAME code for a Freeze Warning. It is issued when temperatures are expected to fall below freezing during the growing season, threatening crops, sensitive vegetation, and exposed plumbing.

What is GGW? #

GGW is the NWS Weather Forecast Office for Glasgow, Montana. Covers northeastern Montana.

What is GID? #

GID is the NWS Weather Forecast Office for Hastings, Nebraska. Covers south-central Nebraska — the heart of the Great Plains severe weather corridor.

What is GJT? #

GJT is the NWS Weather Forecast Office for Grand Junction, Colorado. Covers western Colorado and eastern Utah.

What is GLD? #

GLD is the NWS Weather Forecast Office for Goodland, Kansas. Covers northwest Kansas and the Colorado/Kansas border area.

What is GRB? #

GRB is the NWS Weather Forecast Office for Green Bay, Wisconsin. Covers northeastern Wisconsin and the Upper Peninsula of Michigan.

What is GRR? #

GRR is the NWS Weather Forecast Office for Grand Rapids, Michigan. Covers western lower Michigan and major lake-effect snow from Lake Michigan.

What is GSP? #

GSP is the NWS Weather Forecast Office for Greer, South Carolina (Greenville-Spartanburg). Covers the western Carolinas and the southern Appalachians.

What is GUM? #

GUM is the NWS Weather Forecast Office for Guam. Covers Guam, the Mariana Islands, and nearby Micronesian islands in the western Pacific.

What is GYX? #

GYX is the NWS Weather Forecast Office for Gray, Maine. Covers southern and coastal Maine and southern New Hampshire.

What is HFO? #

HFO is the NWS Weather Forecast Office for Honolulu, Hawaii. Covers all of Hawaii and surrounding Pacific waters, including hurricane and tsunami threats.

What is HGX? #

HGX is the NWS Weather Forecast Office for Houston, Texas. Covers the greater Houston metro, the upper Texas coast, and Galveston Bay.

What is HLS? #

HLS is the EAS/SAME code for a Hurricane Local Statement. Local NWS offices use HLS products to summarize expected tropical impacts, watches/warnings, timing, surge, wind, flooding, and preparedness actions for their forecast area.

What is HNX? #

HNX is the NWS Weather Forecast Office for Hanford, California. Covers the San Joaquin Valley and portions of the Sierra Nevada foothills.

What is HUA? #

HUA is the EAS/SAME code for a Hurricane Watch — hurricane conditions possible within 48 hours. The 48-hour window exists specifically to allow time for evacuation before a warning is issued.

What is HUN? #

HUN is the NWS Weather Forecast Office for Huntsville, Alabama. Covers northern Alabama and is collocated with the Severe Storms branch.

What is HUW? #

HUW is the EAS/SAME code for a Hurricane Warning — issued when sustained hurricane-force winds (74+ mph) are expected within 36 hours. A HUW is a mandatory evacuation trigger in many coastal jurisdictions. If a HUW is issued for your area, do not wait.

What is IBW? #

IBW (Impact-Based Warnings) is the NWS system that adds damage-threat tags and tiered severity language to Tornado and Severe Thunderstorm Warnings. Tags like TORNADO DAMAGE THREAT...CONSIDERABLE or THUNDERSTORM DAMAGE THREAT...DESTRUCTIVE appear at the bottom of warning text. Fully operational nationwide since 2016. These tags are the source of the community shorthands TOR-C, TOR-E, SVR-C, SVR-D, etc.

What is ICT? #

ICT is the NWS Weather Forecast Office for Wichita, Kansas. Covers south-central Kansas — a prolific tornado and severe weather region.

What is IFR? #

IFR (Instrument Flight Rules) conditions exist when ceiling is below 1,000 ft or visibility is below 3 miles, requiring pilots to fly by instruments rather than visual reference. LIFR (Low IFR) is more severe (ceiling <500 ft or visibility <1 mile). Fog, low clouds, and heavy precipitation commonly cause IFR conditions.

What is ILM? #

ILM is the NWS Weather Forecast Office for Wilmington, North Carolina. Covers southeastern North Carolina and the Cape Fear Coast.

What is ILN? #

ILN is the NWS Weather Forecast Office for Wilmington, Ohio. Covers southwest Ohio and parts of southeast Indiana.

What is ILX? #

ILX is the NWS Weather Forecast Office for Lincoln, Illinois. Covers central Illinois.

What is IND? #

IND is the NWS Weather Forecast Office for Indianapolis, Indiana. Covers central Indiana.

What is IWX? #

IWX is the NWS Weather Forecast Office for Northern Indiana (Fort Wayne). Covers northern Indiana and lake-effect snow from Lake Michigan.

What is JAN? #

JAN is the NWS Weather Forecast Office for Jackson, Mississippi. Covers central Mississippi.

What is JAX? #

JAX is the NWS Weather Forecast Office for Jacksonville, Florida. Covers northeast Florida and extreme southeast Georgia.

What is JKL? #

JKL is the NWS Weather Forecast Office for Jackson, Kentucky. Covers eastern Kentucky and portions of the Cumberland Plateau.

What is KDP? #

KDP (Specific Differential Phase) measures phase shift caused by oblate raindrops. High KDP = heavy liquid rainfall — better than reflectivity for flash flood threat assessment because it ignores hail.

What is LBF? #

LBF is the NWS Weather Forecast Office for North Platte, Nebraska. Covers the Nebraska Panhandle and north-central Nebraska.

What is LCH? #

LCH is the NWS Weather Forecast Office for Lake Charles, Louisiana. Covers southwest Louisiana and the Sabine River area.

What is LIX? #

LIX is the NWS Weather Forecast Office for New Orleans/Baton Rouge, Louisiana. Covers southeast Louisiana and the Mississippi Delta.

What is LKN? #

LKN is the NWS Weather Forecast Office for Elko, Nevada. Covers northeastern Nevada and the Ruby Mountains.

What is LMK? #

LMK is the NWS Weather Forecast Office for Louisville, Kentucky. Covers north-central Kentucky and south-central Indiana.

What is LOT? #

LOT is the NWS Weather Forecast Office for Chicago, Illinois. Covers the Chicago metro area, northern Illinois, and northwest Indiana.

What is LOX? #

LOX is the NWS Weather Forecast Office for Los Angeles, California. Covers coastal and inland southern California.

What is LSX? #

LSX is the NWS Weather Forecast Office for St. Louis, Missouri. Covers eastern Missouri and portions of southern Illinois.

What is LUB? #

LUB is the NWS Weather Forecast Office for Lubbock, Texas. Covers the South Plains of Texas — prime tornado country.

What is LWX? #

LWX is the NWS Weather Forecast Office for Sterling, Virginia (Baltimore/Washington). Covers the D.C. metro area, Maryland, and northern Virginia.

What is LZK? #

LZK is the NWS Weather Forecast Office for Little Rock, Arkansas. Covers central Arkansas.

What is MAF? #

MAF is the NWS Weather Forecast Office for Midland/Odessa, Texas. Covers the Permian Basin and Trans-Pecos Texas.

What is MEG? #

MEG is the NWS Weather Forecast Office for Memphis, Tennessee. Covers the Mid-South including western Tennessee, northern Mississippi, and eastern Arkansas.

What is MFL? #

MFL is the NWS Weather Forecast Office for Miami, Florida. Covers southeast Florida and the primary office for South Florida hurricane threats.

What is MFR? #

MFR is the NWS Weather Forecast Office for Medford, Oregon. Covers southwest Oregon and the Cascades.

What is MHX? #

MHX is the NWS Weather Forecast Office for Morehead City, North Carolina. Covers coastal North Carolina and the Outer Banks.

What is MKX? #

MKX is the NWS Weather Forecast Office for Milwaukee/Sullivan, Wisconsin. Covers southeast Wisconsin.

What is MLB? #

MLB is the NWS Weather Forecast Office for Melbourne, Florida. Covers the Space Coast and east-central Florida.

What is MOB? #

MOB is the NWS Weather Forecast Office for Mobile, Alabama. Covers coastal Alabama and the western Florida Panhandle.

What is MPX? #

MPX is the NWS Weather Forecast Office for Twin Cities, Minnesota (Chanhassen). Covers the Minneapolis-St. Paul metro and southern Minnesota.

What is MQT? #

MQT is the NWS Weather Forecast Office for Marquette, Michigan. Covers the Upper Peninsula of Michigan and Lake Superior lake-effect snow.

What is MRX? #

MRX is the NWS Weather Forecast Office for Morristown, Tennessee. Covers eastern Tennessee and the southern Appalachians.

What is MSO? #

MSO is the NWS Weather Forecast Office for Missoula, Montana. Covers western Montana including the Northern Rockies and fire weather threats.

What is MTR? #

MTR is the NWS Weather Forecast Office for San Francisco Bay Area, California. Covers the Bay Area, the central California coast, and coastal mountain ranges.

What is OAX? #

OAX is the NWS Weather Forecast Office for Omaha, Nebraska. Covers eastern Nebraska and southwest Iowa.

What is OHX? #

OHX is the NWS Weather Forecast Office for Nashville, Tennessee. Covers middle Tennessee.

What is OKX? #

OKX is the NWS Weather Forecast Office for New York City, New York. Covers the New York City metro, Long Island, and northeast New Jersey.

What is OTX? #

OTX is the NWS Weather Forecast Office for Spokane, Washington. Covers eastern Washington, the Idaho Panhandle, and northeast Oregon.

What is OUN? #

OUN is the NWS Weather Forecast Office for Norman, Oklahoma. Covers central and western Oklahoma — collocated with the SPC and the National Severe Storms Laboratory.

What is PAH? #

PAH is the NWS Weather Forecast Office for Paducah, Kentucky. Covers western Kentucky, southern Illinois, and the Ohio River Valley.

What is PBZ? #

PBZ is the NWS Weather Forecast Office for Pittsburgh, Pennsylvania. Covers western Pennsylvania, northern West Virginia, and eastern Ohio.

What is PDT? #

PDT is the NWS Weather Forecast Office for Pendleton, Oregon. Covers northeastern Oregon and southeastern Washington.

What is PHI? #

PHI is the NWS Weather Forecast Office for Mount Holly, New Jersey (Philadelphia/Wilmington). Covers the Delaware Valley, South Jersey, and northeast Maryland.

What is PIH? #

PIH is the NWS Weather Forecast Office for Pocatello, Idaho. Covers southern Idaho and the Snake River Plain.

What is PQR? #

PQR is the NWS Weather Forecast Office for Portland, Oregon. Covers the Portland metro, the Oregon coast, and the Columbia River Gorge.

What is PSR? #

PSR is the NWS Weather Forecast Office for Phoenix, Arizona. Covers the Phoenix metro, the low desert, and central Arizona.

What is PUB? #

PUB is the NWS Weather Forecast Office for Pueblo, Colorado. Covers southeast Colorado including the Sangre de Cristo Mountains.

What is PVA? #

PVA (Positive Vorticity Advection) is when an upper-level disturbance (vorticity max) is moving over your location, producing rising motion in the mid-levels. PVA is one of the strongest synoptic-scale signals of approaching weather — especially when paired with a moist, unstable surface layer.

What is QPF? #

QPF (Quantitative Precipitation Forecast) is the forecast amount of liquid precipitation — rain or melted snow — expected over a given time period. The core product for flood and winter storm forecasting. Heavy QPF (2"+ in 6 hours over saturated ground) is a direct trigger for Flash Flood Watches and Warnings.

What is RAH? #

RAH is the NWS Weather Forecast Office for Raleigh, North Carolina. Covers central North Carolina and the Research Triangle.

What is REV? #

REV is the NWS Weather Forecast Office for Reno, Nevada. Covers the Reno/Tahoe area and much of northern Nevada.

What is RFW? #

RFW is the EAS/SAME code for a Red Flag Warning. It means critical fire weather is occurring or expected: low humidity, strong winds, dry fuels, and rapid fire-spread potential.

What is RIW? #

RIW is the NWS Weather Forecast Office for Riverton, Wyoming. Covers central and western Wyoming and Yellowstone.

What is RLX? #

RLX is the NWS Weather Forecast Office for Charleston, West Virginia. Covers West Virginia and parts of eastern Kentucky.

What is RNK? #

RNK is the NWS Weather Forecast Office for Blacksburg, Virginia. Covers western Virginia and the central Appalachians.

What is SCP? #

Supercell Composite Parameter (SCP) combines MUCAPE, effective shear, and effective SRH into a single supercell-likelihood index. SCP > 4 strongly favors supercells; >10 is extreme.

What is SEW? #

SEW is the NWS Weather Forecast Office for Seattle, Washington. Covers the Puget Sound area, the Olympic Peninsula, and the western Cascades.

What is SGF? #

SGF is the NWS Weather Forecast Office for Springfield, Missouri. Covers southwest Missouri and northwest Arkansas.

What is SGX? #

SGX is the NWS Weather Forecast Office for San Diego, California. Covers San Diego County and the inland deserts of southern California.

What is SHV? #

SHV is the NWS Weather Forecast Office for Shreveport, Louisiana. Covers northwest Louisiana, northeast Texas, and southwest Arkansas.

What is SJT? #

SJT is the NWS Weather Forecast Office for San Angelo, Texas. Covers west-central Texas and the Edwards Plateau.

What is SJU? #

SJU is the NWS Weather Forecast Office for San Juan, Puerto Rico. Covers Puerto Rico, the U.S. Virgin Islands, and surrounding Caribbean waters.

What is SLC? #

SLC is the NWS Weather Forecast Office for Salt Lake City, Utah. Covers the Wasatch Front, Great Salt Lake, and most of Utah.

What is SPW? #

SPW is the EAS/SAME code for a Shelter In-Place Warning. It is an all-hazards alert telling people to stay indoors and protect themselves where they are, often because going outside would be more dangerous.

What is SQW? #

SQW is the NWS product code for a Snow Squall Warning. Notable: SQW warnings are not broadcast over NOAA Weather Radio EAS the way most other warnings are — they rely primarily on WEA, NWS.gov, and media dissemination. They're brief, intense, and often issued with only minutes of lead time.

What is SSA? #

SSA is the EAS code for a Storm Surge Watch — possible life-threatening storm surge inundation within 48 hours. Issued by NHC in coordination with tropical cyclone advisories.

What is SSW? #

SSW is the EAS code for a Storm Surge Warning — issued separately from the hurricane wind warning since 2017. Because surge is the deadliest hurricane hazard, evacuation decisions in coastal zones are now often driven by the SSW rather than wind category alone.

What is STO? #

STO is the NWS Weather Forecast Office for Sacramento, California. Covers the Sacramento Valley and northern Sierra Nevada.

What is STP? #

Significant Tornado Parameter (STP) combines MLCAPE, 0–6km shear, 0–1km SRH, MLLCL, and MLCIN to estimate the probability of a significant (EF2+) tornado. STP > 1 = favorable; >3 = high-end environment.

What is SVA? #

SVA is the official EAS/SAME code for a Severe Thunderstorm Watch. Fires on NOAA Weather Radio when an SVR Watch polygon covers your county. The Tornado Watch equivalent is TOA.

What is TAE? #

TAE is the NWS Weather Forecast Office for Tallahassee, Florida. Covers the Florida Panhandle and the Big Bend region.

What is TBW? #

TBW is the NWS Weather Forecast Office for Tampa Bay, Florida. Covers the Tampa Bay metro, the southwest Gulf Coast of Florida, and the Suncoast.

What is TFX? #

TFX is the NWS Weather Forecast Office for Great Falls, Montana. Covers north-central Montana and the Rocky Mountain Front.

What is TOA? #

TOA is the official EAS/SAME code for a Tornado Watch, broadcast over NOAA Weather Radio. When TOA fires, it means a Tornado Watch polygon is in effect for your county. The equivalent for Severe Thunderstorm Watch is SVA.

What is TOP? #

TOP is the NWS Weather Forecast Office for Topeka, Kansas. Covers northeast Kansas.

What is TRA? #

TRA is the EAS/SAME code for a Tropical Storm Watch. It means tropical-storm-force winds are possible, generally within 48 hours, and preparations may need to begin before conditions deteriorate.

What is TRW? #

TRW is the EAS/SAME code for a Tropical Storm Warning. It means sustained tropical-storm-force winds are expected, generally within 36 hours. Secure loose objects and finish preparations before winds arrive.

What is TSA? #

TSA is the NWS Weather Forecast Office for Tulsa, Oklahoma. Covers northeastern Oklahoma and the Ozark foothills.

What is TSW? #

TSW is the EAS/SAME code for a Tsunami Warning. It means a tsunami threat is expected or occurring. Move immediately away from beaches, harbors, and low-lying coastlines if you are in the warned area.

What is TWC? #

TWC is the NWS Weather Forecast Office for Tucson, Arizona. Covers southeast Arizona and the Sonoran Desert.

What is UNR? #

UNR is the NWS Weather Forecast Office for Rapid City, South Dakota. Covers western South Dakota and the Black Hills.

What is VCP? #

VCP (Volume Coverage Pattern) is the scan strategy a NEXRAD radar uses — how many elevation tilts are scanned and how fast.

Severe/Precipitation modes:

• VCP 211 — Fast severe weather, replaces legacy VCP 11
• VCP 212 — Default severe mode, 14 tilts, ~4.5 min
• VCP 215 — Faster severe mode, better temporal resolution for rapid-cycling storms
• VCP 221 — Precipitation mode, replaces legacy VCP 21
• VCP 121 — Fast precipitation mode

Clear air modes (no precip):

• VCP 31 — Long-pulse clear air, ~10 min scan, best sensitivity
• VCP 32 — Short-pulse clear air, ~10 min scan
• VCP 35 — Clear air with more tilts, faster updates than 31/32

During active severe weather, NWS operators select a severe-weather VCP for faster volume scans.

What is VEF? #

VEF is the NWS Weather Forecast Office for Las Vegas, Nevada. Covers southern Nevada, the Las Vegas Valley, and northwestern Arizona.

What is VIL? #

Vertically Integrated Liquid (VIL) estimates total liquid water content in a vertical column. High VIL values (esp. high VIL density) correlate with large hail potential.

What is VOW? #

VOW is the EAS/SAME code for a Volcano Warning. It is used when volcanic activity creates a public hazard, such as ashfall, lava, lahars, or other dangerous volcanic impacts.

What is WSA? #

WSA is the EAS/SAME code for a Winter Storm Watch. Issued 24–48 hours in advance when winter storm conditions are possible. Use the watch window to prepare before the warning drops.

What is WSW? #

WSW is the EAS/SAME code for a Winter Storm Warning. Fires on NOAA Weather Radio when a Winter Storm Warning is in effect for your county. Criteria vary by region (heavier snow thresholds in the north, much lower in the south).

What is ZDR? #

ZDR (Differential Reflectivity) compares horizontal vs. vertical returns, indicating particle shape. High ZDR = flat raindrops (heavy rain). Low ZDR = round particles (hail). Useful for hail discrimination.