Add the connection of the reset pin of the ATmega as per AN2519

weather_station_sensor.sch

 	8500 5100 8500 5050
 Wire Wire Line
 	1800 1700 1700 1700
-Text GLabel 6150 4000 2    50   Input ~ 0
-Reset
-Wire Wire Line
-	6150 4000 6050 4000
 Wire Wire Line
 	5450 5200 5450 5250
 Wire Wire Line
 Connection ~ 3550 6500
 Wire Wire Line
 	3550 6500 3700 6500
+Wire Wire Line
+	6350 3950 6350 4000
+Connection ~ 6350 4000
+Wire Wire Line
+	6350 4000 6050 4000
+Wire Wire Line
+	6350 4000 6350 4050
+$Comp
+L power:VCC #PWR0103
+U 1 1 5E823307
+P 6350 3600
+F 0 "#PWR0103" H 6350 3450 50  0001 C CNN
+F 1 "VCC" H 6367 3773 50  0000 C CNN
+F 2 "" H 6350 3600 50  0001 C CNN
+F 3 "" H 6350 3600 50  0001 C CNN
+	1    6350 3600
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	6350 3600 6350 3650
+$Comp
+L power:GND #PWR0104
+U 1 1 5E826963
+P 6350 4400
+F 0 "#PWR0104" H 6350 4150 50  0001 C CNN
+F 1 "GND" H 6355 4227 50  0000 C CNN
+F 2 "" H 6350 4400 50  0001 C CNN
+F 3 "" H 6350 4400 50  0001 C CNN
+	1    6350 4400
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	6350 4400 6350 4350
+Text GLabel 6400 4000 2    50   Input ~ 0
+Reset
+Wire Wire Line
+	6400 4000 6350 4000
+$Comp
+L Device:R R1
+U 1 1 5E8179ED
+P 6350 3800
+F 0 "R1" H 6420 3846 50  0000 L CNN
+F 1 "4k7" H 6420 3755 50  0000 L CNN
+F 2 "Capacitors_SMD:C_0603_HandSoldering" V 6280 3800 50  0001 C CNN
+F 3 "~" H 6350 3800 50  0001 C CNN
+	1    6350 3800
+	1    0    0    -1  
+$EndComp
+$Comp
+L Device:C C7
+U 1 1 5E81E0CA
+P 6350 4200
+F 0 "C7" H 6465 4246 50  0000 L CNN
+F 1 "100n" H 6465 4155 50  0000 L CNN
+F 2 "Capacitors_SMD:C_0603_HandSoldering" H 6388 4050 50  0001 C CNN
+F 3 "~" H 6350 4200 50  0001 C CNN
+	1    6350 4200
+	1    0    0    -1  
+$EndComp
 $EndSCHEMATC