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How does expected rainfall compare to normal rainfall for this month?

This map shows places in the world that are forecasted to receive over the next six days a large percentage of the rainfall that normally falls over this entire month in their location.

See the "More Information" tab for forecast details.

What does "Heavy" mean?

The map shows how much of the rainfall that normally falls over an entire month is expected to fall in only the next six days. Areas that are expected to receive large proportions of a normal month's accumulated rainfall over the next 6 days are forecast to experience heavy rain. The darker the blue, the heavier the expected 6-day rain. The red and violet colors indicate where the cumulative rainfall expected over the next 6 days is likely to be 2 to 3 times (200%-300%) the average monthly rainfall for that location and time of year (compared to 1985-2012). Medium blue indicates where the total 6-day rain is expected to be 1 to 1-1/2 times (100%-150%) the average monthly rainfall for that location and time of year. Normal or less than normal rain is shown in white.

This forecast shows rain over large areas only, and should not be used to forecast cyclone tracks, local rainfall, or as a flood forecast. The map does not distinguish areas where rainfall is expected from areas where snow is expected. Forecasts for the amount of snow are indicated in terms of the equivalent amount of rainfall, so the actual depth of snow would be considerably more than indicated. The forecast data are courtesy of the NOAA ESRL Reforecast Version 2 Project.

How to use this interactive map

Switch to another map: Select the dropdown menu at the top of the page

Return to the menu page: Click the blue link called “IFAD” at the top left corner of the page.

Zoom in to a region:
Method 1: Pick a region from the list:

  1. Select the dropdown menu at the top of the page, titled “Region”
  2. Click on the region of interest, and the map will automatically refresh.

Method 2: Click-and-drag:

  1. Click the left mouse button at the upper-left corner of the region to which you would like to zoom.
  2. While holding down the button, drag the mouse to the lower-right corner of the region to which you would like to zoom.
  3. Release the left mouse button. The map will redraw automatically.

Zoom out to the global map:

  1. Move your mouse over the map, until you see three icons appear in the upper left corner.
  2. Click the icon of the magnifying glass.
  3. The map will redraw automatically. Note that the map cannot display areas outside of the latitudes initially shown on the interface.

Change the date of the forecast: Forecasts are labeled by the day they were issued. You can find this label by moving your mouse over the map until you see a text box appear at the top with the date inside.

  1. To step forward or back by one day, click the corresponding buttons to the left or right of the text box, and the map will automatically refresh.
  2. To manually change the forecast issue date, type your date of interest into the text box. This must follow the format: “0000 16 Jan 2008”. Then, press “enter” or click the “refresh” icon in the top left corner of the map.
  3. To produce an animation of these maps over a series of dates, type the date range into the text box. This must follow the format: “start date” followed by “to” followed by “end date”. For example “0000 1 Jan 2008 to 0000 15 Jan 2008”.

Single-Day (24-Hour) Total Precipitation Forecast Maps

Dataset Documentation

Data Daily ensemble-mean forecast precipitation totals at 1.0° lat/lon resolution from the 2012 version of the National Centers for Environmental Prediction's (NCEP) Global Ensemble Forecasting System (GEFS) model run daily using 00 UTC initial conditions, available via the NOAA ESRL PSD Reforecast Version 2 Project
Data Source U. S. National Oceanic and Atmospheric Administration (NOAA), Earth System Research Laboratory (ESRL), Physical Sciences Division (PSD), ESRL Reforecast Version 2 Project
Analyses: Analyses shown here include forecast daily (days 1-6) and six-day precipitation totals, forecast daily and six-day total precipitation anomalies from the 1985-2012 mean, forecast daily and six-day total precipitation as percent of mean monthly total precipitation (1985-2012 base period), and forecast daily and six-day total precipitation percentiles (1985-2012 base period).

Helpdesks

Contact help@iri.columbia.edu with any technical questions or problems with this Map Room, for example, the forecasts not displaying or updating properly.