Update app.py

app.py

@@ -276,8 +276,19 @@ class TyphoonAnalyzer:
         return oni_data, typhoon_data
 
     def process_oni_data(self, oni_data):
+        """Process ONI data"""
         oni_long = pd.melt(oni_data, id_vars=['Year'], var_name='Month', value_name='ONI')
-        oni_long['Month'] = oni_long['Month'].map(lambda x: pd.to_datetime(x, format='%b').month)
+        
+        # Create a mapping for month numbers
+        month_map = {
+            '01': 1, '02': 2, '03': 3, '04': 4,
+            '05': 5, '06': 6, '07': 7, '08': 8,
+            '09': 9, '10': 10, '11': 11, '12': 12
+        }
+        
+        # Convert month strings to numbers directly
+        oni_long['Month'] = oni_long['Month'].map(month_map)
+        
         return oni_long
 
     def process_typhoon_data(self, typhoon_data):