Three years (2014-15 to 2016-17) experimental data collected at Pulse Research Station, Vadodara was used to calibrate and validate the CROPGRO- pigeon pea model for three cultivars of pigeon pea (BDN 2, AGT 2 and Vaishali). The validated model was used to simulate the seed yield by changing the maximum and minimum temperature (-30 to +30C) in different months (June to January) and rainfall (-25% to +25%) during July, August and September. Results revealed that the elevated temperature had negative effect on seed yield and reduced temperature had positive effect. Among the varieties, AGT 2 was least affected by the temperatures and rainfall. Vaishali was found to be most sensitive to elevated temperature.Higher rainfall during August was beneficial on seed yield of pigeon pea. Pigeon pea sown in June was most affected due to elevated temperatures and July sown was most affected by rainfall. The effect of minimum temperature on seed yield was less than that observed with maximum temperature.