Argentina Forecast Turning Wetter

January 20, 2012

A stormy weekend is shaping up for the western Argentina grain belt especially Buenos Aires where drought and heat stress has been severe.

Cordoba and Santa Fe also have the potential for scattered strong thunderstorms and locally heavy rainfall.  The atmosphere is turning unstable with increasing humidity in a developing trough of low pressure.

 

Here is the 3-day forecast Saturday-Monday, very wet in Buenos Aires:

 

South Brazil faces a relatively dry forecast in the upcoming week in Rio Grande do Sul and Parana.  A swath of very heavy rain is predicted from Mato Grosso in the Brazil interior to Sao Paulo on the coast. 

 

High Humidity Makes Atmosphere Unstable

Below are 3 maps showing the "precipitable water" in the atmosphere , the amount of rain possible if all the moisture is squeezed out as rain.    With high humidity, the atmosphere becomes more unstable and ripe for showers.  

Monday looks especially humid in Cordoba, Santa Fe and Buenos Aires -- the 3rd forecast map down.

The 30-day rainfall map still indicates areas of extreme dryness  despite good rainfall last week in Argentina dn South Brazil.     See where Argentina corn and soybeans are produced. 

Summer Heat Stress

Hot temperatures have prevailed the past 3-4 days in Argentina’s grain belt.  Highs yesterday were mid 90s F in Buenos Aires.  Extreme heat extended up through Uruguay to Rio Grande do Sul in South Brazil.  Paraguay also was very hot, near 100 F.

 

 

Due to increasing cloudiness and showers,  the Buenos Aires  temperatures will moderate over the weekend, backing off into the low and mid 80s F.   The forecast  continues very hot in the Argentina central grain belt, Paraguay and western Rio Grande do Sul:

 

Extreme heat has dominated the  South America interior for more than one month, extending from Paraguay south into Buenos Aires and La Pampa in Argentina.