First eastern Pacific Tropical Storm of Season?

From NHC this afternoon (Friday May 28, 2010)

...SPECIAL FEATURE...
AN AREA OF DISTURBED WEATHER IS SOUTH OF THE GULF OF TEHUANTEPEC
WITH A BROAD 1005 MB SURFACE LOW NEAR 13N94W. SCATTERED MODERATE TO
STRONG CONVECTION IS FROM 12N TO 16N BETWEEN 91W AND 96W. THE SYSTEM
CONTINUES TO PRODUCE ABUNDANT TROPICAL MOISTURE INLAND OVER SW
MEXICO AND GUATEMALA. A 28/1616 UTC ASCAT SATELLITE PASS WENT OVER
THE LOW CENTER DEPICTING 20-25 KT WINDS WITH STRONGEST WINDS SE OF
THE CENTER. THE CONSENSUS OF NUMEROUS TROPICAL TRACK MODELS HAS THIS
LOW MOVING NE TOWARDS THE COAST OF GUATEMALA. THERE IS A HIGH CHANCE
FOR THIS SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE OVER THE NEXT 48
HOURS. REGARDLESS OF THE POTENTIAL FOR DEVELOPMENT...THIS SYSTEM IS
EXPECTED TO PRODUCE VERY HEAVY RAINFALL AND FLOODING OVER PORTIONS
OF CENTRAL AMERICA DURING THE NEXT FEW DAYS.