Forecasts and Warnings

Detailed forecasts, weather warnings and current conditions for Pennsylvania counties are available from the Pennsylvania Weather Pages


Daily Climatological Observations

The daily climatological observations are reports from the cooperative observer network, and are taken at about 7AM (EST). The observers may report the preceding 24 hour high and low temperatures, along with the 24 hour total precipitation and snowfall information. Some reports also have the temperature at time of observation (the current temperature category). The National Weather Service maintains a site for cooperative observers, and the daily observed data is available for the lower US.

Hourly Air Quality Observations

The Pennsylvania Department of Environmental Protection coordinates a network of air quality monitoring stations in Pennsylvania. The amounts of ozone, nitrogen oxides, sulfur compounds and other pollutants are reported hourly.

Sea Surface Information

ESRL has an animation of the SST anomalies in the Pacific region of the El Nino/ La Nina phenomenon. The animation is updated approximately weekly.

Earthquake Information for the Northeastern States

The US Geological Survey provides earthquake information from around the world. The most recent information for earthquakes in Pennsylvania and nearby states is made available through the Geological Survey.

Hourly Weather Observations

The full set of current weather observations, posted hourly, are for stations in Pennsylvania and surrounding states which border the Commonwealth. The corresponding set of undecoded METARs is also available. While most meteorologists and weather buffs know the station identifiers, many do not and so they are included here.

Current surface maps of temperatures, dew points, relative humidities, and wet bulb temperatures for the Pennsylvania region are also posted hourly. These maps are produced at about 35 minutes past the hour. Occasionally bad data will be recorded in the weather database, and appears as a bull's-eye pattern in the contouring. The problem is usually corrected with the next hourly posting.

Additional maps for obstructions to vision (the weather!), visibilities (in tenths of a mile), sea-level pressures, three hour sea-level pressure change, wind directions, and wind speeds are also posted. The sea-level pressures are in tenths of a millibar with the leading 9 or 10 omitted (132 = 1013.2 millibars = 29.92" mercury), the pressure changes are in tenths of a millibar over a 3 hour period prior to the stated time, and the wind speeds are in knots. The wind directions have been overlaid with the surface convergence pattern (convergence in red, divergence in black).

And finally, there are maps for wind gusts (in knots), wind chill temperatures, gust chill temperatures and highest reported cloud bases and total sky cover.

There are about 80 stations that could report each hour, although typically only about 75 report during the day and 65 at night. A map of all possible station 3-letter id's is posted for reference.

Penn State ASOS Site

The Meteorology Department at Penn State maintains an ASOS (KPSU) observing site at Rock Springs. Data is transmitted at 5 minute intervals.

Satellite Picture

A regional satellite picture in the visible part of the spectrum is available for Pennsylvania, along with an infrared picture. Additional cloud imagery (which includes satellite loops) is available from NCAR's Research Applications Program (RAP).

NWS NEXRAD WSR-88D Doppler Radar

The National Weather Service provides base reflectivity radar data for each of its radar sites. The central Pennsylvania radar page is provided by the NWS State College Forecast Office.

Freese-Notis has a NEXRAD composite of the U.S. updated each hour.

Radar data from WSI may be found below for cities within or close to Pennsylvania.

Almanac

The US Naval Observatory Almanac page permits the calculation of sunrises/sunsets for any area and time, along with many other astronomical quantities.